Trimble faces a lot of work to persuade his party

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David Trimble will need more from the IRA than he received on Monday if he is to take the step of trying to persuade his party to go back into government with Sinn Fein.

But if more movement is forthcoming from the IRA, and he decides to try, he will once again have to navigate his way through his Ulster Unionist Party's tortuous decision making processes.

His first meeting took place last night when the party officials gathered to consider the IRA move. He is due to meet shortly with another part of the party in the form of its members of the Belfast Assembly.

These two parts of the structure are thought to contain majorities in favour of the Good Friday Agreement.

The few party members who sit in the House of Lords are also generally in favour, but many of its MPs are against. The MPs lost out at the general election, however, their numbers dwindling from nine to six. The party's executive may also play a part in any decision to have Mr Trimble reverse his resignation as the Assembly's First Minister.

Ultimately, the key decision could be taken by the party's ruling Ulster Unionist Council, which consists of 800 members. Over the past two years its members have steadily lost confidence in the party leader. He has scraped through votes with wafer-thin majorities, securing just 53 per cent support in a leadership challenge. The council majority in favour of the Agreement has been steadily eroded.

Mr Trimble may or may not decide to summon the ruling council to endorse his actions. His permanent tactical advantage, however, is that his opponents can call a meeting at any point.