N.Ireland first minister leaves hospital ahead of talks

* Unionist leader underwent emergency surgery this week

* British, Irish government call talks on budget dispute (Adds details on Irish, British government talks)

BELFAST, May 29 (Reuters) - Northern Ireland First Minister Peter Robinson was released from hospital on Friday as the Irish and British governments stepped in to try and break an impasse that could threaten the region's power-sharing administration.

Robinson (LSE: RBN.L - news) , 66, underwent an emergency operation on Monday, the hospital treating him said. A spokesman for his Democratic Unionist Party declined to comment on local media reports that Robinson had suffered a suspected heart attack.

"Happy to be discharged and back home. Thanks to the wonderful RVH (Royal Victoria Hospital) cardiac team -- everyone a star," Robinson said on his Twitter (Xetra: A1W6XZ - news) account.

He was absent when the power-sharing government failed to pass a social welfare bill on Tuesday that several senior figures have said could lead to the collapse of the assembly in the British-controlled province.

A deal struck between the Northern Ireland parties and the British government late last year was supposed to have eased the way for welfare reforms by promising the local administration a package including loans which would have helped mitigate the cuts enacted in other parts of the United Kingdom.

"Following consultation with the British Government, it has been decided that a review and monitoring meeting of the Stormont House Agreement will take place on June 2. Invitations have today been extended to the Northern Ireland Executive parties," Ireland (Other OTC: IRLD - news) 's foreign office said in a statement.

Finance Minister Arlene Foster, also a member of the DUP party which has led the government with Sinn Fein under the terms of a 1998 peace deal, said failure to pass the budget would leave a 600 million pounds hole in Belfast's finances.

Secretary of State Theresa Villiers has said there is still time to reach agreement over the budget and welfare cuts but has not ruled out taking control of some devolved powers if no deal can be reached between nationalist and unionist parties.

Senior ministers say this could prompt a walkout by one of the major parties and a collapse or suspension of the administration. (Reporting by Maurice Neil; Editing by Padraic Halpin/Mark Heinrich)