Assembly Members will decide later if they'll rush through Welsh Government plans to break its stalemate with the UK Government over how EU powers should be shared out after Brexit.
Carwyn Jones' government has set out its plan to claim all powers in devolved areas such as farming and fisheries set out in a Continuity Bill which the Prime Minister has described as unnecessary.
It's expected a majority of AMs will agree to treat the bill as emergency legislation which means it will be debated, scrutinised and could become law more quickly than usual.
Talks designed to reach agreement failed two weeks ago despite ministers in London making what it described as a 'considerable offer.'
That offer means the disputed powers would be transferred directly to Wales and Scotland, although ministers in London would retain a veto on their use in some limited areas.
The UK Government says that ability is needed to make sure that rules and regulations which affect businesses on a UK-wide basis continue to be applied fairly.
However the Welsh and Scottish Governments say it shows a lack of respect for devolution. They say they understand that rules in some areas should be operated on a UK-wide basis but that such systems should be agreed.
First Minister Carwyn Jones says he'd still prefer to avoid the constitutional row the continuity bill will inevitably cause if it's passed.
There'll be another chance for the three governments to try to reach agreement in a meeting of the Joint Ministerial Committee this coming Thursday.
If that fails, there'll be a face-to-face meeting between the Prime Minister and the First Ministers of Wales and Scotland on March 14th.
If they fail to reach agreement and the continuity bill is passed, it will lead to a constitutional row which is likely to be referred to the Supreme Court.
Plaid Cymru leader Leanne Wood says the Prime Minister should use this 'last chance' to stop her 'power grab' and avoid 'chaos in the courts.'
If AMs agree today to treat the bill as emergency legislation, it could pass through its various stages of debate and scrutiny within weeks.