A key ally of Jeremy Corbyn has sparked a backlash by criticising a plan to hold vote on a second EU referendum.
Barry Gardiner spoke out against a People's Vote - plus a separate idea to revoke Article 50, cancelling Brexit - ahead of a crunch vote by MPs on the way forward tonight.
In a rare process, MPs will choose between up to 16 options in an "indicative vote" to see what can command support in the Commons.
Jeremy Corbyn is under pressure to give MPs a "free vote" on the options.
Yet Shadow Trade Secretary Mr Gardiner said today not all the options would be a free vote.
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He told the BBC: "We will expect all Labour MPs to vote for the proposal which is down in Jeremy Corbyn's name.
"I think that would be inevitable.
"I don't think they would necessarily be whipped but certainly there would be a free vote expected on many of those."
He suggested he would "rule out no deal" and "rule out revocation of article 50" - despite almost 6million people backing the move to cancel Brexit in a petition.
"We have committed ourselves to trying to deliver the referendum result," he explained.
Separately, Labour MP Peter Kyle is spearheading a key option tonight - for a "confirmatory" second EU referendum on whatever deal is agreed by MPs.
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Mr Kyle claimed this morning that Jeremy Corbyn - who last month announced he would support a bid for a second referendum - "will order MPs to vote for this."
But Mr Gardiner said: "It would be saying we could accept what we have always said is a very bad deal.
"Therefore it looks as if the attempt to have a public vote on it is simply a way of trying to remain because nobody likes this deal.
"To put that up as the only alternative in a public vote and say we will let it go through looks as though you believe that at the end of it Remain would be the result.
"It is not where our policy has been.
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"Our policy is clearly that we would support a public vote to stop no-deal or to stop a bad deal, but not that we would allow a bad deal as long as the public had the opportunity to reject Brexit altogether.
"That implies that you are a Remain party. The Labour Party is not a Remain party now. We have accepted the result of the referendum."
A number of Labour MPs reacted to Mr Gardiner's comments.
After he said the party could not support an amendment linking the Brexit deal to another referendum, Wes Streeting tweeted: "This the complete opposite of what we've been told is happening today.
"The opposite of what Keir-Starmer told the Commons.
"The opposite of what EmilyThornberry said last night.
"The opposite of what Labour stands for. Urgent leadership needed. We live in hope."
Jess Phillips tweeted: "It is NOT Labour policy only to vote for peoples vote only in circumstances of no deal. NOT AT ALL.
"It is Labour Policy & has been for years to support compulsory sex & relationship education, guess we'll see how both are whipped today to see how much we care about members views."
And deputy leader Tom Watson wrote: "I've had many calls about Barry Gardiner's interview on BBCr4today, which I missed.
"Whipping arrangement have not yet been agreed. I support the Kyle/Wilson amendment."
A Labour spokesman refused to say at this stage how MPs would be whipped. It is understood an announcement is only due this afternoon.
