Chris Grayling has said a “small number” of military staff have been sent to Whitehall departments to help them prepare for a no-deal Brexit.

The transport secretary, whose department faces major pressures in the event of a chaotic exit, said he speaks “quite regularly” to Gavin Williamson, the defence secretary, over plans to mitigate a disorderly exit from the European Union.

Mr Grayling also insisted recent lorry trials near Dover to prepare for potential travel chaos “went fine”, despite widespread mockery as only 89 lorries turned up out of the 150 invited.

His intervention comes as reports emerged that military planners have been deployed to the Department for Transport, the Home Office and the Foreign Office to prevent chaos at Britain’s borders in a no-deal scenario.

Theresa May has warned that the UK faces crashing out of the EU without a deal if MPs reject her Brexit blueprint on Tuesday – a vote she is widely expected to lose.

Asked if he had held discussions with the defence secretary, Mr Grayling told Sky News’ Sophy Ridge on Sunday: “We discuss as cabinet colleagues what we would do in no-deal planning terms.

“I don’t have the military actively involved in no-deal planning beyond the secondment of a small number of staff from the MoD, as is happening across Whitehall.

“Our focus on no-deal planning has been to have all the aviation agreements we need in place, making sure that we take a look at the possibility of disruption in Kent.

“We don’t want a repeat of what happened in 2015 when the whole of Kent was ground to halt by troubles in the Channel ports.”

He refused to be pushed on the government’s Brexit plan B, saying: “The important thing is to say to fellow MPs those concerns are out there and the big concerns are: are we going to leave? Are we going to deliver Brexit? Are we going to somehow try and reverse Brexit?

“Is parliament going to force us to reverse Brexit?

“What we have is a sensible compromise deal. It’s not giving everybody everything what they want, but it was never going to – this was a 52-48 result.”

Mr Grayling has been under pressure over his department’s no-deal plans after it was revealed he had handed a £13.8m contract to Seaborne Freight, a firm that had never previously operated a ferry service.

New contracts, published quietly on Christmas Eve, reveal Whitehall officials warned that a “situation of extreme urgency” exists in “roll-on roll-off” ferry capacity if the UK leaves the EU without a deal.

Police separate clashing Brexit protesters outside Parliament Show all 11 1 /11 Police separate clashing Brexit protesters outside Parliament Police separate clashing Brexit protesters outside Parliament Anti-Brexit protester Steve Bray (left) and a pro-Brexit protester argue as they demonstrate outside the Houses of Parliament Getty Images Police separate clashing Brexit protesters outside Parliament A pro-Brexit protester argues Getty Images Police separate clashing Brexit protesters outside Parliament Police surround the pro-Brexit protester after he confronted Steve Bray, a pro-European protester Getty Images Police separate clashing Brexit protesters outside Parliament A leave supporter is spoken to by a police officer as he argues with a remain supporter, Steve Bray, outside Parliament PA Police separate clashing Brexit protesters outside Parliament MPs in Parliament are to vote on Theresa May's Brexit deal next week after her December vote was called off in the face of a major defeat Getty Images Police separate clashing Brexit protesters outside Parliament A leave supporter is spoken to by a police officer PA Police separate clashing Brexit protesters outside Parliament Police look on as anti-Brexit protesters demonstrate outside the Houses of Parliament. Getty Images Police separate clashing Brexit protesters outside Parliament Police hold back a leave supporter PA Police separate clashing Brexit protesters outside Parliament A police officer speaks with anti-Brexit protester Steve Bray Getty Images Police separate clashing Brexit protesters outside Parliament Police surround a pro-Brexit protester after he confronted a pro-European protester Getty Images Police separate clashing Brexit protesters outside Parliament Conservative MP David Davies, wearing a gopro camera, speaks to anti-Brexit protester Steve Bray Getty Images

Shadow transport secretary Andy McDonald branded the contract “unsuitable” and called for it to be immediately revoked.