The UK climate minister has left the Cop28 conference in Dubai during the critical last stage negotiations to vote on the Government’s Rwanda Bill, Downing Street has confirmed.

Graham Stuart will arrive back in the UK to vote on what is seen as a crucial test of Rishi Sunak’s leadership as Prime Minister.

As many as 40 Tory MPs are believed to be prepared to abstain or vote against the Bill, arguing that it does not go far enough in preventing people from stopping themselves being deported through legal action.

It is staggering that the UK Government has no ministers attending the final critical days of Cop28

Mr Stuart previously said he was proud to have persuaded the Cop presidency to allow parliamentarians such as himself to have a more significant role in the talks and his departure is likely to be seen as a forfeiture of the UK’s attempts to be a climate leader.

NGOs said the UK has gone “Awol” at the very time that it is needed, accusing the Government of letting down the millions of people who are suffering because of climate change.

Number 10 confirmed that Mr Stuart is returning to attend Parliament, adding: “Ministers have a number of roles, the negotiations continue and he will return to Cop.”

Asked about the carbon emissions from the flights, the Prime Minister’s official spokesman said: “This Government is not anti-flying.

The UK has played a productive role in the talks so far but leaving early is simply shameful. Time and again, wealthy countries have let down low-income countries

“We don’t lecture the public to that regard. The most important thing is the outcomes of Cop, which minister Stuart is obviously leading for the UK on.”

Secretary of State for climate Claire Coutinho had left the conference in the early stages, placing Mr Stuart in charge of the UK delegation.

Francesca Rhodes, senior climate and gender policy adviser for CARE International UK, said: “If the reports are accurate, it is staggering that the UK Government has no ministers attending the final critical days of Cop28.

“These negotiations will decide the fate of millions of people facing floods, fires and famine due to the climate crisis.

“The UK has played a productive role in the talks so far but leaving early is simply shameful. Time and again, wealthy countries have let down low-income countries.

Minister Stuart has returned to the UK to attend Parliament in his role as an MP. There will continue to be full official representation on the ground at the summit, including by Lord Benyon at ministerial level

“The latest text was deeply disappointing and does not keep 1.5C alive. When the UK should be standing up for marginalised communities, including women and girls, Rishi Sunak’s Government has gone Awol.”

A Government spokesperson said: “Minister Stuart has returned to the UK to attend Parliament in his role as an MP.

“There will continue to be full official representation on the ground at the summit, including by Lord Benyon at ministerial level.

“Minister Stuart will continue to be the lead UK minister for negotiations and remains in constant contact with the UK lead climate negotiator and Lord Benyon, with any final decisions agreed with him.”

Labour’s Kerry McCarthy said in the Commons on Tuesday that Mr Stuart should explain to everyone why he has left Dubai, saying he will not be able to approve any decisions made by the UK team while on an aeroplane.

There can be no more tragic outcome for UK climate diplomacy than this

Andrew Mitchell, speaking on behalf of the Government, replied: “A Government, as she will know, is seamless, and while the minister for climate change is anxious to support the Government in the important legislation tonight, my noble friend Lord Benyon – one of the UK’s greatest experts on climate change – is in Dubai today at the Cop to ensure that a senior minister is representing Britain in these vital negotiations.”

Delegates at Cop28 are awaiting the publication of the next draft version of the final agreement, with the deadline having already passed this morning.

The previous version published on Monday made many countries and NGOs furious for excluding a commitment to phase out fossil fuel use, suggesting instead that countries “could” do so within an undefined time.

Chiara Liguori, Oxfam’s senior climate change policy advisor, said: “There can be no more tragic outcome for UK climate diplomacy than this – flying home from talks to avert a climate catastrophe at the most critical moment in an attempt to salvage a cruel and impractical policy.”