The government has said that the civil service team leading negotiations with the European Union over exit terms will not be changed despite prime minister Theresa May’s plan to reopen talks.
Brexiteers in the European Research Group of Conservative MPs have claimed that Number 10 had pledged to draft in two top trade negotiators for talks with Brussels. But Downing Street said there would be "no change" to the British negotiating team, which has long been led by May's Europe adviser, Olly Robbins.
"The civil service team, which is led by Olly Robbins, remains the same," the prime minister's spokesperson said.
Eurosceptics want Julian Braithwaite, the UK’s permanent representative to the World Trade Organisation, and Crawford Falconer, the second permanent secretary and chief trade negotiation adviser for the Department for International Trade – to be brought in to the team.
Steve Baker, a key player in the ERG, said: "Excluding our chief trade negotiation adviser from our principal trade negotiation is a longstanding mistake which should be rectified now."
Conservative MPs called for the change after reports Robbins had warned colleagues against the prime minister's plan to push the EU for changes to the Northern Ireland backstop.
According to the Telegraph, Robbins questioned whether the EU would agree to significant legal changes to the backstop, which would keep Britain closely aligned to the bloc if no other way to avoid a hard border between Ireland and Northern Ireland can be found.
A source told the Telegraph: "The gist of the email was that it wasn't worth the paper it's written on."
Responding to the story, ERG chair Jacob Rees-Mogg said the group “understood that Crawford Falconer would be involved in future negotiations and it would be surprising if this did not happen".
But the focus on Robbins drew fire from the boss of the union representing senior officials.
FDA general secretary Dave Penman said: "The premise that somehow the fault lies with the messenger, rather than the message, shows how delusional some are in this debate.
"The constant search for a scapegoat, rather than a solution, is shameful."
The comments come amid reports Ministry of Defence permanent secretary Stephen Lovegrove has said that preparing for a no-deal Brexit is his department's "highest priority" in a letter to staff.
In the letter, sent before Christmas and seen by Sky News, he said the department had already made significant progress with no-deal preparations.
"This includes both our internal planning to mitigate the impacts on defence itself as well as the wider support we have provided to the cross-government effort,” he said.
"However, moving into the new year, we will not only have to continue this hard work but treat it as our highest priority."
He instructed the armed forces and other MoD personnel to implement the remaining elements of their no-deal plans "in full and without delay".
"If necessary, this will need to include delaying or deprioritising areas of work or reallocating internal resources to better meet no deal demands," Lovegrove wrote.
The MoD has already revealed that it has developed plans to call up reservists from the UK’s armed forces to deal with the consequences of a no-deal Brexit.
In a statement earlier this month, armed forces minister Mark Lancaster said the move was part of “the Cabinet Office co-ordinated work programme to ensure that there are effective and proportionate contingency plans in place to mitigate the potential immediate impacts leaving the EU, under a no-deal scenario, might have on the welfare, health and security of UK citizens and economic stability of the UK”.
The statement confirmed that an order had been made under the Reserve Forces Act 1996 to enable reservists to be called into permanent service, putting them on standby to either replace regular soldiers moved into Brexit work, to provide specialist skills or to be part of “24/7 operation and resilience” at “regional points of command”.