Former Welsh Secretary David Jones has said Dominic Raab was "absolutely right" to resign as Brexit secretary in protest at Theresa May's Brexit deal.

Mr Raab said it gave the EU a "veto" over when the UK could leave temporary customs rules, and on Northern Ireland it threatened the integrity of the UK.

Mr Jones said the so-called backstop was a "massive problem".

Meanwhile the Welsh and Scottish first ministers have sent a letter scathing of Mrs May's handling of the deal.

Carwyn Jones and Nicola Sturgeon told the prime minister it was "symptomatic of the chaotic approach to the negotiations" and lacked any "meaningful engagement" with their administrations.

They demanded a chance to have some input into the political declaration about future UK-EU relations before it was finalised.

Mr Raab quit the cabinet on Thursday morning after less than five months in the job saying he "cannot in good conscience support" the UK's draft Brexit agreement with the EU.

Work and Pensions Secretary Esther McVey resigned shortly after, and two junior ministers have also quit the government.

The proposals had been approved by the cabinet following a five-hour meeting on Wednesday, although several ministers are understood to have spoken against them.

David Jones, a former Brexit minister, told BBC Radio Five Live the deal involved clear breaches of Conservative manifesto commitments.

"We are going to be effectively stuck in a customs union almost indefinitely," the Clwyd West MP said.

"The prime minister has always been clear that we can't treat Northern Ireland separately from the rest of the UK and this is what this agreement will potentially do.

"I think Dominic was absolutely right - he had no option but to go and I applaud him for doing it."

David Jones said the deal passed by the Cabinet on Wednesday would not satisfy Parliament, adding that "Downing Street has got to wake up to the reality of the situation".

Later, in the House of Commons, Tory MPs lined up to condemn the draft withdrawal agreement as the prime minister delivered her statement on it.

But she got support from former Welsh Secretary Stephen Crabb, who said "the theory of a perfect Brexit" had "met the cold reality of hard choices and compromise".

"This is absolutely not the moment to walk away from our responsibilities to govern and provide this country with leadership at this difficult time," the Preseli Pembrokeshire MP said.

Mrs May agreed, saying there were "difficult choices to be made ... not according to how we wish the world could be like, but to the reality of the world that we see, and to make those choices pragmatically in the interests of the British people".

The prime minister rejected a call from Rhondda Labour MP Chris Bryant for MPs to vote now on the draft deal before she attended an EU summit on 25 November to finalise the agreement.

Warning that time was "of the essence", Mr Bryant asked: "Would it not make sense now, before she goes to the European Council, to have a vote in this house?

"If she wins, she's got the support of Parliament - if she loses, then we have to take another tack."

Earlier, Welsh Secretary Alun Cairns described the Brexit deal as a compromise and not a cave-in to the EU, which he said had conceded ground to include the whole UK in a fall-back customs partnership rather than just Northern Ireland.

He told BBC Radio Wales: "I wish we didn't have to have the backstop in relation to Northern Ireland, because it's an insurance policy for the Republic of Ireland and the Belfast agreement.

"It's not our intention to use it, but it's part of the agreement."

The backstop is an arrangement designed to ensure there is no return to a hard border between Northern Ireland and the Republic of Ireland.

It will only take effect if an open border does not form part of the future trading agreement between the UK and EU.

Plaid Cymru has confirmed it will oppose the deal, with their parliamentary leader Liz Saville Roberts lamenting it as one which "pleases none of the people, all of the time", as she repeated calls for another referendum.

UKIP's leader in the Welsh Assembly, Gareth Bennett, said the plans were "a complete betrayal" of Brexit.

South and Mid Wales Chambers of Commerce said the Welsh business community needed to give measured and considered thought to the draft agreement.

Meanwhile the chief executive of Aston Martin - the luxury car maker which has a plant in the Vale of Glamorgan - has said the draft Brexit deal was "good enough".

However, Andy Palmer added that the firm would not halt contingency planning for a no-deal scenario, saying: "The Tory party needs to agree and then Parliament needs to agree, and I don't think any of that is that easy."