Haass due to visit Number 10
A former US diplomat chairing all-party talks on flags and parades in Northern Ireland is expected to meet members of the Prime Minister's office tomorrow.
Dr Richard Haass has until Christmas to deliver recommendations on how to deal with contentious issues left outstanding from the 1998 Good Friday Agreement which enshrined the peace process.
Relations between power-sharing partners the Democratic Unionists and Sinn Fein have become increasingly strained in recent times following a summer of street violence linked to loyal order marches and protests.
Northern Ireland Secretary Theresa Villiers said: "Dr Haass is expected to visit Number 10 tomorrow."
She added that the British and Irish governments were working together to support the process and help build consensus.
"This is a Government which is entirely engaged in the process because ... I believe it represents an important way forward in resolving the continuing tensions," she said.
Mrs Villiers has met Dr Haass twice and had telephone conversations, while her officials have also had contact with the former Northern Ireland envoy.
A spokeswoman for Dr Haass said: "Richard Haass is having private meetings on Thursday in London. He is also meeting with the Cabinet Office and Prime Minister's office to discuss Northern Ireland matters."
Dr Haass is gauging opinion on flags, parades and the legacy of a past from which 3,000 killings remain unresolved.
He held more than 30 engagements last month with politicians from the five largest parties in the devolved administration at Stormont, senior clergy, the Orange Order and business leaders, and is expected to attend further meetings in Belfast, London and Dublin this month.
Northern Ireland has endured a particularly turbulent year, with months of loyalist rioting linked to the Union flag dispute and parading controversies.
Violence erupted last December after Belfast City Council voted to reduce the number of days it flies the Union flag from the City Hall.
Sporadic trouble injuring scores of police continued for weeks - at one stage nationalists and unionists in east Belfast engaged in hand-to-hand fighting.
Republicans have been criticised for not cancelling an IRA commemoration of two men killed by their own bomb in Co Tyrone despite appeals from relatives of terror victims.
Political relations in the political power-sharing institutions frayed after DUP First Minister Peter Robinson withdrew his support for a controversial peace centre on the site of the former paramilitary prison at the Maze.
Senior Sinn Fein MLA Gerry Kelly has said the situation at Stormont had reached crisis point but the claim was denied by unionists.