Shadow Brexit Secretary Sir Keir Starmer has turned down a job offer at the law firm behind Gina Miller's successful Article 50 court challenged, it was announced on Tuesday 25 July.

"I am grateful to Mishcon de Reya for discussing a possible role advising the Mishcon Academy with me, but, given my other commitments, I have decided not to further the discussions," Starmer said in a statement.

The former Director of Public Prosecutions was paid £18,000 for four month's worth of legal advice for Mishcon in 2016, according to the House of Commons' register of members' interests.

News of the potential advisory role prompted the Conservatives to issue a "conflict of interest" warning, stressing that Starmer would be given privileged information as member of The Queen's Privy Council.

"Mishcon de Reya has been an active participant in legal cases surrounding the United Kingdom's exit from the European Union," said Tory MP James James Cleverly. "The firm stressed that the result of the referendum was not legally binding and supported anonymous claimants in their legal efforts last year.

"The firm acted for Gina Miller in her case against the government regarding the triggering of Article 50 even though your party leader Jeremy Corbyn called for Article 50 to be triggered immediately following the referendum, without the consent of Parliament. The firm's legal work alongside your role in the shadow cabinet creates a possible conflict of interests.

He added: "In your position as the Shadow Secretary of State for Exiting the European Union you will be personally involved with drafting and speaking on legislative amendments on the EU Withdrawal Bill.

"You have also recently been made a member of the Privy Council, which will allow you privileged access to documents and information."

Mishcon de Reya declined to comment when contacted by IBTimes UK. Labour, meanwhile, are facing in-fighting over the party's Brexit position.

Shadow International Trade Secretary Barry Gardiner claimed it would be "disaster" if the UK remained inside the EU's customs union just a day after Corbyn said "we haven't jumped on either side of that fence".

Chuka Umunna, the Open Britain supporter, warned against such a position, warning that it would make Labour indistinguishable from the Tories over Brexit. "Taking [the] single market and customs union membership off the table in the Brexit talks is the Tory position, it should not be Labour's," he said.