The first ministers of Wales and Scotland have both declared they would welcome a general election.
However, Mark Drakeford and Nicola Sturgeon said they wanted to see the details of any Brexit extension before backing a vote before Christmas.
Ms Sturgeon said she wanted to ensure the risk of no-deal had been removed.
They were speaking at a news conference in Westminster where they opposed Boris Johnson's Brexit Bill.
The Scottish First Minister branded Prime Minister Boris Johnson's Withdrawal Agreement Bill as "bad" legislation and added that it would be opposed by the devolved administrations in both Edinburgh and Cardiff.
For the first time in the history of devolution, the governments in Scotland and Wales could both refuse formal consent for legislation that affects their nations.
MPs backed the Prime Minister's Brexit proposals on Tuesday night.
His planned timescale for approving the Bill within days was rejected, however, forcing him to put a pause on the legislation.
Mr Johnson must now wait to hear from the leaders of the 27 other member states of the European Union on whether they will approve another delay to the UK's departure date.
With the PM having pledged to deliver Brexit "do or die" by October 31, he is to push for a general election if they sanction a Brexit extension.
Earlier this week, the two First Ministers jointly wrote to Mr Johnson and the president of the European Council asking for an extension to give more time to scrutinise the Bill.
In a statement, the Uk Government said it wants to "get Brexit done to give Wales and the whole of the UK the brighter future they deserve."