The Government's plans for Brexit are "in paralysis", Labour claimed, amid speculation crucial legislation will be delayed again.
Shadow Brexit Secretary Sir Keir Starmer said there was "chaos at the heart of Government" over the approach to leaving the European Union.
The flagship Brexit legislation - the European Union (Withdrawal) Bill - had been widely expected to return to the Commons next week.
The Department for Exiting the European Union (Dexeu) insisted that no date had formally been set for the legislation's next stage.
But Sir Keir said: "This is further proof that the Government's Brexit strategy is in paralysis.
"The negotiations are in deadlock and now a crucial piece of legislation is facing further delay.
"There is chaos at the heart of Government. Theresa May cannot unite her Cabinet or her party behind this deeply flawed Bill.
"There are now serious questions about whether the Prime Minister can deliver Brexit."
Commons Leader Andrea Leadsom will confirm next week's business in the regular statement on Thursday.
Mrs Leadsom told MPs last Thursday that there had been "300 amendments and 54 new clauses" proposed for the so-called repeal bill, which will put existing EU regulations on the domestic statute book.
She said it was "taking a bit of time to have proper, thoughtful, well-considered responses" to those, but the Bill would return "just as soon as we're able to".
That had been taken as a sign the Bill could return in next week's business.
MPs are due to spend eight days debating the repeal bill at committee stage, which will then undergo further scrutiny in the Commons and the Lords before it is approved.
Government will 'prepare for all possible scenarios' in Brexit talks, PM says
It would be "irresponsible" of Government "not to prepare for all possible scenarios" as Britain conducts its Brexit talks with the European Union, the Prime Minister has said.
Her comments came as SNP Westminster group leader Ian Blackford urged Theresa May to "rule out a no deal".
Speaking during Prime Minister's Questions in the Commons, the MP for Ross, Skye and Lochaber said: "Will the Prime Minister do today what her Brexit Secretary was unable to do in this chamber yesterday and rule out a no deal scenario on leaving the EU?
Mrs May said: "I can confirm that what we are doing is working for the best possible deal for the UK. But it would be irresponsible of Government not to prepare for all possible scenarios and that's exactly what we're doing."
Mr Blackford reminded the Prime Minister that Home Secretary Amber Rudd had said it was "unthinkable" the UK will walk away from talks with Brussels without a deal at least covering security co-operation.
He added: "Can I point out to her that what her Home Secretary said yesterday, that a no deal is unthinkable.
"I agree with the Home Secretary. Brexit has contributed to a fall in the pound and a subsequent rise in inflation squeezing household budgets. Folk are getting poorer in Britain today."
Mr Blackford provoked some laughter in the chamber as he appeared to say that Government analysis showed that Scotland and the north-east of England would lose out from "breakfast", before correcting himself, saying "Brexit".
He said: "The Government benches are engaging in hilarity - the reality is that the people in this country are going to pay an economic price for a hard Brexit."
After being urged to finish his question by Speaker John Bercow, he added: "What is the Government's analysis of the impact of Brexit on a no deal scenario?"
Mrs May responded: "I'm sorry that in his rather lengthy question he did not make any reference to the fact that since 2010, nearly a quarter of a million more people in Scotland are in work - that is the result of the actions of this Government."