MPS are to have just five hours to debate and vote on the Brexit deal in the House of Commons tomorrow.

Proceedings are due to get under way around 9.30am, with Downing Street sources confirming a vote is expected around 2.30pm.

The Bill, which is due to be published today, will then pass to the House of Lords where it is expected to be discussed and scrutinised late into the night.

If it is passed, it will receive royal assent “very late” on Wednesday or “possible into Thursday morning”, No.10 said.

The deal document itself will be signed in Brussels tomorrow by EU chiefs, before it Is flown by the RAF for Boris Johnson to sign.

HeraldScotland: Ursula von der Leyen

The Prime Minister’s official spokesman said the international treaty would be signed by European Commission president Ursula von der Leyen and European Council president Charles Michel before being flown across the Channel.

An RAF plane will transport the treaty, accompanied by UK and EU officials, and the document is expected to be signed by the Prime Minister in Downing Street on Wednesday afternoon.

The SNP has already confirmed it will vote against the deal, prompting criticism that the party would therefore prefer to back a no-deal exit from the EU.

Ian Blackford MP, the party's Westminster leader, rejected the idea in a radio interview yesterday and said: "We are certainly not supporting No Deal. No Deal is something that would be a disaster for all of us

"The best deal that we’ve got is the one we currently have where we’re still in the single market and customs union. All the economic evidence, including from the UK Government, is that we are all going to be poorer with this deal.”

Read more: SNP MPs confirm they will reject Brexit deal in Commons vote

Labour is facing a rebellion from within after leader Keir Starmer said his party would support it.

A number of high-profile members, including shadow chancellor John McDonnell, have signed a statement urging Mr Starmer not to back the EU agreement.

Some Labour MPs have raised concerns that Mr Starmer suggested there would be support for the deal before the legislation has even been published, however the leader said his party must support it as "it is not credible for Labour to be on the sidelines".

HeraldScotland: Sir Keir Starmer

The statement organised by left wing groups Another Europe is Possible and Labour for a Socialist Europe, states it is the duty of the opposition to provide proper Parliamentary scrutiny and to set out an alternative.

It read: “That task gets harder if opposition parties fall into the trap of rallying around this rotten deal.

"We are witnessing an act of vandalism against our livelihoods, our rights and our horizons.

"We call on Labour, the Labour movement and other opposition parties not to support the Tories' Brexit deal when it is put to a vote in the House of Commons."

Signatories include former cabinet ministers, and leading pro-Europeans, Ben Bradshaw and Lord Adonis, as well as former MEPs, councillors and local activists.