Three years ago Peter Curistan (51), chairman of property developers the Sheridan Group and the man who created the Odyssey, the province's landmark Millennium project in Belfast, was hailed as Northern Ireland's Entrepreneur of the Year. Then, last year, his company was accused in the House of Commons of being associated with "IRA dirty money" and a £100m development project on the banks of the River Lagan was put on ice after the Department for Social Development withdrew Sheridan's preferred developer agreement.

You had relatively humble beginnings for a man who later built up an impressive property development organisation.

I was born at Hatfield Street, off the Ormeau Road, Belfast, 51 years ago and the family later moved to Andersonstown. I went to the Holy Child School, failed my 11-plus and moved to La Salle secondary school, which had just opened. I didn't sparkle academically, initially being more interested in playing gaelic football and hurling, and, later, soccer. I played in the first La Salle team to win the schools' soccer cup. One of the other players was Mal Donaghy, who later became an Irish international. I also played in the Amateur League and remember one match in Carrickfergus where we had to be given protection by the UDA. Recognising the importance of academic achievement, I progressed to the A level stream and obtained a place at Queen's University, Belfast, in 1974 and took an honours degree in economics with accounting and law. I was the first person in my family to go on to third level education.

How did your career develop?

After Queen's I succeeded in getting a job with Price Waterhouse, then, as now, a leading accountancy firm. It was very tough, working during the day and studying for accountancy examinations at night. I qualified as a chartered accountant in 1980. I married Anne in 1979 and two years later we decided to go abroad. We chose Hong Kong and it was an incredible experience. Anne worked with the English Schools Foundation teaching ex-pats and earned more money than I did with Price Waterhouse. I was a member of the Hong Kong football club and played against superstars like George Best, Charlie George, Bobby Moore, Tommy Hutchinson and Alan Ball. After two years, we came back to Northern Ireland. I had a managerial role in the firm by this stage, but after another couple of years I decided that mainstream accountancy was not for me. I really wanted to run my own business.

How did you make that move?

I became a director of a listed mineral exploration company with interests in Ghana, Europe and Co Mayo, and I also set up my own accountancy consultancy practice, working from home. Then, one night in October 1986, Anne and I queued up for the opening of Crocodile Dundee at the Curzon Cinema in Belfast. There were huge queues and we didn't get to see the film. I had travelled to the US and saw multiplex cinemas in action and I thought they would work in Belfast. Initially, the Department of Economic Development was not terribly interested in my proposal, but I signed up cinema operators Cannon and went back to them. I had identified a site on the Dublin Road and, six years after my initial idea, I opened a multi-screen cinema there. It is now the Movie House. I also took over the operations of the adjoining car park, Burger King and Chicago Pizza Pie Factory outlets.

Your operations snowballed after that.

Having established the Sheridan Group and having successfully developed the Dublin Road site, I decided to look towards Dublin. I created a development at Parnell Street, then a fairly rough part of the city. It consisted of a multi-storey car park, multiplex cinema, bars, restaurants, family entertainment centres, retail space and 101 apartments. I also developed a £12m waterfront complex in Bournemouth. Other projects have included the Tannery retailing, parking, apartment and black taxi depot in King Street, Belfast, and the Posthouse Premier (now Holiday Inn) hotel on Ormeau Avenue.

Your company also brought the Odyssey, Northern Ireland's landmark Millennium project to Belfast. Is that the jewel in your development portfolio?

It is certainly our highest profile development. When I came up with the idea 12 years ago, people said that I was mad. Now, a number of people who are claiming credit for the creation of Odyssey are the same people who tried to pour cold water on it. I risked about £1m to win the competition to build the complex run by the Millennium Commission, and put some £35m into the project. The public sector, including the Lottery, put up some £70m. I then convinced SMG of Philadelphia to come over to run the arena. They would only come in as a joint venture with me and this has proved to be a huge success. Through running Odyssey I have met a lot of the acts which have performed there and I am particularly friendly with Westlife. My wife and I went to Shane Filan's wedding and I am director of a company with Brian McFadden, who left the group in 2004. I have also got to know singer Ronan Keating.

Yet the scene of your greatest triumph has become your greatest challenge, following the decision in December last year by the Department for Social Development and Laganside Corporation to terminate an agreement with your company, Sheridan Millennium, to develop three sites at Queen's Quay beside the Odyssey.

We worked on the project for almost two years and won the competition in June 2005 to become preferred developer on three sites in the area. This was not unusual: all the sites we have developed have been won through competition. It was a £100m project to provide residential, commercial and entertainment facilities on the sites stretching back from the River Lagan.

In July 2005, a Dublin newspaper published an article about my relationship with Dessie Mackin, a senior Sinn Fein official who was a director of a number of my companies in Dublin. Then, in February last year, East Belfast MP Peter Robinson spoke in the House of Commons to highlight this relationship and call on the Secretary of State to investigate what he called the "activities of the Sheridan Group and its association with the IRA's dirty money". The result was like throwing a hand grenade into a crowded room.

Mr Robinson was very supportive when we first showed him our development plans. I have tried to contact him since he made his statement in the House of Commons, but he has never responded. I also urged him to give any evidence of wrong-doing on my part to the PSNI. Senior PSNI officers have confirmed to me that they have never investigated me, nor are they currently doing so.

How did your association with Mr Mackin come about?

I had originally met him when I was at Queen's University. I worked part-time in the Oak Bar on the Grosvenor Road and he actually took over my job. When I developed the Parnell Centre in Dublin many years later I needed security for the centre. A friend in Northern Ireland introduced me to Mr Mackin, who was associated with him in security. I remembered him from the bar. I also urgently needed a southern-based director for the companies in Dublin. He was only a co-director for about six months in the period that the newspaper article reported. Mr Mackin is no longer associated with any of my companies.

Do you now regret that association?

Perhaps I was naive in believing that a lot of old emnities seemed to be disappearing, but this was at a time when a new Assembly was being set up in Northern Ireland. We had Sinn Fein ministers. I didn't think there would be any issue. Perhaps, most importantly, no one has produced a shred of evidence of wrong-doing on my part.

What has been the result of the allegations and loss of the development contract?

The consequences for me, my family and my business have been significant. I have had a number of death threats from paramilitaries. On one occasion I stopped for petrol on the Newtownards Road in east Belfast and a man approached me, cocked his hands and pretended to shoot me.

Doormen at the Odyssey have been asked if I am in the centre and to tell me not to come back. I have been pointed out when I go into public places and people I thought were friends have shunned me.

I no longer get the same number of invitations to lunch or the Christmas cards and presents that I previously did from business associates. On the other hand, I have had a lot of support from many people whom I would not have expected to be with me.

We were also shortlisted for developing the national sports stadium if the Ormeau Park site in Belfast was chosen, but I am concerned about the possible implications for this of recent events. We have been speaking to major global investment bankers about our development plans, but they have been told not to have any further discussions with us because of the adverse publicity.

As a result of newspaper articles, my son has been intimidated and my daughter has been accused of being the daughter of a criminal.

What do you propose to do?

I am well down the path of legal action against three newspapers which carried articles which I believe paint a tainted picture of myself and my companies. We are also initiating action against Laganside Corporation. I believe my reputation, which has taken me 30 years to build up, has been tainted.

In a letter to the company telling us that our development agreement had been terminated, Laganside said that after two sets of due diligence reports from accountants they were in no position to properly form an opinion of the deliverability of the project and so could not recommend whether or not the department should continue with the development plans.

On July 31 last year we submitted our audited accounts to Laganside. The corporation has requested no further information since then. We don't even know what the due diligence reports into our company said. Now, we are told the department is to organise another competition to find a developer for the site and has told us that we can re-enter.

What a joke. In the meantime, Belfast suffers because of the delay in implementing such a major project.

We are on the brink of applying for planning permission to develop the Queens Quay site and have spent about £1m on it so far. We also had discussions with international investors who were keen to invest heavily on the project. It is ironic that in recent years the Odyssey Pavilion won the UK's Best Leisure Regeneration Scheme in a UK-wide awards competition and that in 2004 I won the Institute of Directors/Lunns Award for Entrepreneur of the Year 'in recognition of sustained commitment to excellence and outstanding contribution to life in Northern Ireland'. Now, some people are trying to blacken my name. This is going to be the biggest fight I have ever had, but I and my colleagues are not going to walk away from it.