Chief electoral officer tells parties 15 December being looked at for vote
The secretary of state has restated his intention to call a second Northern Ireland Assembly election this year if the Executive is not reformed by 28 October.
Chris Heaton-Harris says he "can't see the space" for any emergency legislation to potentially avert the move.
No date for a fresh election was mentioned, however Northern Ireland's chief electoral officer has told the parties they are looking at 15 December.
At the NI Affairs committee, Mr Heaton-Harris told MPs he had discussed the situation at Stormont with his Cabinet colleagues earlier on Tuesday.
He said: "If we do not get a reformed Executive by one minute past midnight on 28 October, I will be calling an election.
"That's what the law requires me to do, and that is what I will be doing. I know that lots of people really do not see or do not want that to happen but it is a legislative requirement."
Northern Ireland last went to the polls on 5 May.
UTV's Political Editor Tracey Magee says Chief Electoral Officer Virginia McVea has written to the parties to say they're considering 15 December as the date.
"I wouldn't read too much into that, the chief electoral officer can't throw this together at the last minute so of course she's trying to make plans," added Tracey.
The DUP is blocking the functioning of the power-sharing institutions at Stormont as part of its protest against the Northern Ireland protocol.
The post-Brexit trade deal has created barriers on the movement of goods between Great Britain and Northern Ireland.
The UK Government has vowed to secure changes to the Protocol, either through a negotiated compromise with the EU or domestic legislation to empower ministers to scrap the arrangements without the approval of Brussels.
Chris Heaton-Harris says his focus is "trying to charm, beguile, coax everybody into that place, that they come back into the Executive".
He added: "I'd like to think I will be successful, but if I'm not then I'm afraid it is an election."
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