President Bush's special envoy to Northern Ireland will join intensive talks aimed at restoring devolved government to the province.
US special envoy Mitchell Reiss will join the talks
Mitchell Reiss will take part in the all-party discussions at Leeds Castle in Kent later this month, it emerged on Thursday.
The talks, aimed at resolving issues surrounding the deadlock over the IRA's continued existence and power-sharing at Stormont, will be chaired by the British and Irish prime ministers.
Northern Ireland Secretary Paul Murphy said on Wednesday that the talks would be the moment of decision for the peace process.
Mr Murphy told MPs that the government was not contemplating failure at the talks, which were a "crucial part of the process".
A week of intense activity aimed at generating movement in the Northern Ireland political situation should culminate in Mr Blair's Sedgefield constituency on Friday.
The prime minister is expected to meet Bertie Ahern to assess the chances of progress at the Leeds Castle talks.
The political institutions in Northern Ireland were suspended in October 2002 amid allegations of IRA intelligence gathering at the Northern Ireland Office.
The DUP and Sinn Fein have maintained high-level contacts with both governments over the summer.