The visit follows two rounds of meetings in Helsinki at which politicians from Northern Ireland and South Africa explained to representatives of Iraqi factions how their experiences might help in ending the conflict.

Mr McGuinness will attend a meeting at the heavily defended al-Rashid Hotel on the edge of the Green Zone where he will release details of an agreement reached under the auspices of a Helsinki-based conflict resolution organisation.

The Helsinki II Agreement: Principles and Mechanisms will be unveiled at an event hosted by Akram Al Hakim, Iraq's Minister of National Reconciliation and Dialogue.

Endorsed by top officials from several Iraqi factions, the principles cap a 10-month process that saw two secretive conferences in Helsinki, Finland, where various Northern Ireland and South African peace negotiators shared their conflict resolution experiences with members of warring Sunni and Shi'a factions in Iraq.

The Helsinki II principles closely mirror the Mitchell Principles advocated by Good Friday Agreement co-chairman George Mitchell, which called for a renunciation of violence by all negotiating parties, a verifiable decommissioning process and commitments to human rights.

While not a cure-all for the complex and multi-layered divisions that feed the political and social maelstrom that now engulfs Iraq, Helsinki II proponents hope that the proposals offer a basic template from which Iraqis can develop their own unique conflict resolution process.

Joining Sinn Fein's Martin McGuinness at the launch will be John Alderdice, the former Assembly speaker and Alliance Party chief who now sits on the three-man Independent Monitoring Commission. Scheduling conflicts have prevented the DUP's Jeffrey Donaldson, who attended both the September 2007 and April 2008 talks in Helsinki, from participating.

South African attendees will include Cyril Ramaphosa, the former chief peace process negotiator for the African National Congress.

The visiting Northern Irish and South African politicians may not immediately realise that Baghdad remains the most dangerous city in the world. The Iraqi capital no longer resounds to the sounds of explosions every morning as it did 18 months ago, and only 448 Iraqi civilians were killed in June, says the Health Ministry, but reconciliation, along the lines of Northern Ireland or South Africa, has a long way to go.

The Iraqi capital has become a city of concrete walls and checkpoints separating Sunnis and Shias. The entrances and exits to enclaves are heavily guarded by soldiers and police. Members of different communities do not enter each other's territory. Few of the two million refugees, mostly from the greater Baghdad area, have returned from Syria and Jordan and when they do it is often with fatal results.

On Monday, a Sunni family from the al-Janabi tribe tried to move back into their house in the al-Amil district, formerly dominated by the Mehdi Army Shia militia who follow the anti-American cleric Muqtada al-Sadr. The family had fled during the sectarian civil war in Baghdad in 2006 and early 2007. Within hours of trying to return to their home the entire family – a man, his wife and several children – had been killed.

On the same day in the predominantly Sunni al-Mekanik district of Dora in south Baghdad, an area formerly controlled by al-Qa'ida in Iraq, a Shia family, misjudging the comparative calm of Baghdad over the past month, similarly tried to take back their old home. This time not only the husband and wife were killed, but so was their driver, whose beheaded body was left in the street.

People in Baghdad fear that, while the Sunni insurgents and Shia militias may have gone away, they have not gone very far. Two other Sunni families, who tried to return to their houses, were greeted with bombs, and graffiti on a wall, presumably from the Mehdi Army, reading, "A moment of interruption and we shall return".

The Shia were the winners in the battle for Baghdad and now form about three quarters of its population. About 25 per cent of the Sunni population of the city fled to Syria and Jordan and have never come back, Mohammed, a Sunni teacher, said. Sectarian affiliation remains crucial in getting jobs. Iraq is run by a Shia-Kurdish government, and job applications generally have to be backed by a letter of recommendation from one of the ruling parties. Jobs in Iraq are scarce and most are with the government.

Flush with its earnings from oil exports, the government pays some four million salaries and pensions. Here again the Sunni feel discriminated against, just as the Shia did during the long Sunni predominance which ended with the fall of Saddam Hussein.

More shops are now open but prices of many items have doubled from what they were a couple of years ago. This is partly because almost no goods come from Iraq itself. Even in the street markets the water melons come from Iran and the tomatoes and potatoes from Jordan.