The Department for Exiting the European Union will be wound up when the UK leaves the EU on January 31, the Government has announced.

Established in 2016 following the Brexit referendum, the department is responsible for overseeing negotiations to leave the EU and establish the future relationship between the bloc and Britain.

Boris Johnson has vowed to take Britain out of the bloc at the end of next month, and will begin driving the necessary legislation through Parliament when his Withdrawal Agreement Bill (WAB) is debated on Friday.

The UK will then enter a transition period which the Government has insisted will come to an end in December 2020, which senior EU figures have warned is insufficient time to broker a trade deal.

It is understood Boris Johnson is planning a major overhaul of Whitehall departments (PA)

The Prime Minister altered the WAB to include a clause banning ministers from accepting an extension to that transition period.

Outgoing Labour leader Jeremy Corbyn warned the Commons that Mr Johnson had “deliberately resurrected the threat of no-deal” at the end of 2020 with that move.

The PM, however, hit back insisting to MPs that his Government “will work flat out” to deliver “a new golden age” for the UK.

“Tomorrow is the day when we finally peel back the plastic wrapping about which you have heard so much and present our oven-ready deal and it will go into the microwave as the Withdrawal Agreement – it works in both devices this deal,” Mr Johnson said.

Mr Johnson said the deal will “take back control” of money, borders, law and trade, “clearing the way for an overarching programme of national renewal”.

A Government spokesman confirmed the department known as DExEU will be “wound up once the UK leaves the EU on January 31″ after staff were spoken to on Thursday.

“We are very grateful for all their work and we will help everyone to find new roles,” the spokesman added.

It follows reports that the Prime Minister is planning a major shake-up of Whitehall – with suggestions that the best DExEU staff may join the Cabinet Office to boost numbers in Britain’s EU negotiating team.

Other ideas floated include splitting energy and climate change from the business department again and merging the Department for International Trade with the business department.

The Foreign Office and the Department for International Development could also be aligned to shift the aid budget’s focus and ensure it aligns with foreign policy goals.

FDA trade union national officer Victoria Jones, who represents members in the department, said: “DExEU was always going to be a fixed-term department, but the timing of this announcement so close to the Christmas period will not be a gift to staff.

“While the civil service has committed to finding roles for those who want to remain within the civil service, the reality is that these talented public servants will now face a significant amount of uncertainty of when a suitable alternative role can be offered to them.

“We’ll be working with our members and civil service employers to ensure that the skills and expertise currently sat within DExEU are retained after January, and ensure that civil servants can start the new year with job security that acknowledges the significant contribution they have made.”