Brexit talks on a future trade relationship will only be complicated if the European Union decides to "punish Britain for having the audacity" to leave, Liam Fox has said.

The International Trade Secretary warned Brussels to put the prosperity of EU citizens ahead of any desire to make the UK pay a price for quitting the bloc, and sign a mutually beneficial trade agreement.

Shadow foreign secretary Emily Thornberry warned that "intransigence" from Theresa May has left Britain "heading for no deal".

And Dr Fox said leaving without an agreement and trading on World Trade Organisation (WTO) terms was "not exactly a nightmare scenario".

But the Scot stressed he would "prefer to have a deal because it would give greater certainty and almost certainly greater openness" and said reaching agreement does not need to be complicated if there is political will.

"I don't think they're (the negotiations) difficult in terms of the trade law or the trade negotiations themselves. The difficulty is the politics," Dr Fox told ITV's Peston On Sunday.

"In other words, how much does the European Commission and the European elite want to punish Britain for having the audacity to use our legal rights to leave the European Union.

"That's the thing.

"And what will the price be for the prosperity of European citizens of that decision?

"I would hope that economic sense would dictate that we put the prosperity agenda of the whole of the European continent in a global context at the top of that agenda not ever closer union, in other words the drive by the Commission towards their political objective which has a near-theological level."

Dr Fox also dismissed suggestions from French president Emmanuel Macron that "secondary players" in the UK were "bluffing" about the possibility of a no deal outcome because Mrs May did not mention it when she addressed EU leaders over dinner on Thursday.

The International Trade Secretary said Mr Macron was "completely wrong about that" and the Government was working out the potential costs of no deal and how to mitigate them for different industries.

Reports suggest the Government may use the coming weeks to step up preparations for no deal in an attempt to force the EU's hand in negotiations by showing the UK is ready to leave without a trade agreement, in the hope that it could lead to a more favourable outcome including fewer concessions on an exit payment.

But Ms Thornberry warned that it was Tory splits holding up Brexit negotiations rather than inflexibility in Brussels.

"I think what we may be seeing is the Europeans trying to make it clear that it is not their fault that there are these difficulties, the intransigence does not come from their side, it comes from Theresa May's side," she told BBC One's Andrew Marr Show.

"And in the end I think the reality is intransigence is on Theresa May's side, because she doesn't have the strength or the authority to be able to control her backbenchers, let alone her Cabinet, and I think we are heading for no deal, and I think that that is a serious threat to Britain and it is not in Britain's interests for that to happen.

"We will stop that."

Shadow Brexit secretary Sir Keir Starmer said Labour will join forces with Tory rebels in an attempt to force the Prime Minister into giving MPs a veto on the final Brexit deal.

The shadow Brexit secretary demanded six changes to the "paused" repeal Bill, formally known as the European Union (Withdrawal) Bill, including Parliament being given final approval of the exit agreement, warning that the Government faces defeat if it does not listen to MPs.

Pro-EU Labour MP Chuka Umunna said there has been "an unprecedented" level of cooperation among backbenchers of all parties over Brexit.

"In the end you've got to put aside the party political stuff on this issue, because history is not going to be kind to people who if you do, say, do things in their own self-interest here," he told Marr.

"For me this is one of those issues, a bit like when you're voting for military action, you don't simply blindly follow your whips, you do what you believe is the right thing by your principles and your constituents."

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