The Sinn Fein president was banned from attending a meeting in the House in January, but the Campaign Group of Labour MPs last night invited him to visit as soon as possible.
Jeremy Corbyn, a leading member of the 30-strong group, said: 'We are re-issuing our earlier invitation to him to come to speak to MPs to explain what the Sinn Fein demands are likely to be ahead of the negotiations with the Government.'
The lifting of the exclusion order was welcomed by Tony Blair, the Labour leader. 'The Government's caution about the cessation of violence was justified but they are right now to take these significant steps and to move the process on,' he said.
'I welcome the lifting of exclusion orders and the opening of border crossings and the signals that the peace dividend arising out of the current process will be used for constructive economic development.'
Ulster Unionist MPs gave the Prime Minister's speech a cautious welcome but reinforced their demands that the IRA should be required to surrender its weapons before joining negotiations.
David Trimble, an ally of James Molyneaux, the Ulster Unionist leader, said: 'We are glad to see John Major is maintaining his cautious approach. His speech underlined the need for the IRA to address the issue of weapons. We have to wait and see what proposals the Government is going to bring forward for the disposal of these weapons.'
The surrender of weapons was also seen as a priority by the Rev Ian Paisley, the leader of the Democratic Unionist Party. He said: 'The IRA have made it clear that it (the question of weapons) is only the end of the package. So all the time they are talking, they will be armed.'
Sammy Wilson, the DUP spokesman, said: 'John Major's climb- down over the permanency of the IRA ceasefire is another victory for the IRA.'
Andrew Hunter, chairman of the Tory backbench Northern Ireland committee and a committed Unionist, underlined the importance of the arms issue. He said: 'Very early on in the talks about talks, this question will have to be raised. If the IRA are serious about peace, there will be no reason for the IRA to have guns.'
Pat Doherty, the Sinn Fein vice- president, accepted the issue of arms would be on the agenda in the coming talks, but insisted they would also have to cover a date for the withdrawal of British troops.
The speech brought warm praise from the Irish government. Dick Spring, the Irish foreign minister, said he hoped it signalled the two governments would be more in step. 'I welcome the announcements . . . They are very significant and certainly indicate a willingness to move the whole process forward,' he said.
The Taoiseach, Albert Reynolds, said it gave 'much-needed momentum' to the peace process.
The Church of Ireland Primate, Archbishop Robin Eames, said Mr Major's statement contained 'so much which ought to reassure the community'. The archbishop said Mr Major's speech should reassure the community that the vacuum of peace could be filled with 'positive, imaginative and courageous co-operation in which all our people can play a part'.
The Liberal Democrats' leader Paddy Ashdown said: 'We have been pressing the Prime Minister to increase the momentum for peace and to ensure that substantive talks start before the end of the year. The Prime Minister has now done both of these, and more. I especially welcome the UK Government's undertaking to publish its proposals for the internal settlement about the government of Northern Ireland.'
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