US reaction: Welcoming the statement yesterday, the White House said it understood the IRA and its members would no longer have any contact with foreign paramilitary and terrorist organisations.
This assurance, which was not included in the IRA announcement, is believed to have been given to the Bush administration by Sinn Féin's chief negotiator Martin McGuinness, who met President Bush's special envoy Mitchell Reiss in Washington yesterday morning.
The White House had been pressing Sinn Féin for the IRA to specifically disassociate itself from any links with international terrorism.
Asked about the White House statement, Mr McGuinness said it was made clear to volunteers that they were under strict orders not to be involved in any other activity whatsoever, and "I don't think we would have any concerns on that score".
White House spokesman Scott McClellan did not elaborate on what foreign groups the Bush administration had in mind, but concern about IRA links have been simmering since the episode of the 'Colombia Three' and the current atmosphere of the "war on terror". "We welcome today's IRA statement pledging 'an end to the armed campaign'," Mr McClellan said.
"This is an important and potentially historic statement consistent with the IRA's commitment to 'the development of purely political and democratic programmes through exclusively peaceful means' and to 'not engage in any other activities whatsoever'.
"This IRA statement must now be followed by actions demonstrating the republican movement's unequivocal commitment to the rule of law and to the renunciation of all paramilitary and criminal activities.
"We understand that many, especially victims and their families, will be sceptical.
"They will want to be certain that this terrorism and criminality are indeed things of the past."
Mr Reiss said the IRA statement was "very positive".
In a telephone interview after meeting Mr McGuinness over breakfast, he said: "It is a potentially historic statement. Whether it's truly historic or not depends on translating the very good words into deeds."
Mr Reiss also discussed the IRA move by telephone with Sinn Féin leader Gerry Adams, Peter Robinson of the DUP, and Ulster Unionist Party leader Sir Reg Empey. He said he planned to talk to the DUP's Rev Ian Paisley at a later date.
He said he interpreted the order to IRA volunteers that they "must not engage in any other activities whatsoever" to mean that they should cease criminal activities.
Senator Edward Kennedy welcomed the IRA statement on the floor of the Senate.
"Hopefully this statement means we're finally nearing the end of this very long process to take guns and criminality out of politics in Northern Ireland once and for all."
Senator Chris Dodd said the announcement "has the potential to finally bring true peace to a land long starved of stability".