Boris Johnson is expected to hold a press conference this afternoon as he returns to Cop26 in Glasgow.
The prime minister will travel back to Scotland on Wednesday for another round of negotiations at the UN climate summit.
Negotiators are set to scrutinise a first draft of a “cover decision” – a negotiated outcome to the talks that aims to boost climate action.
The document urges countries to set out long-term strategies by the end of next year to reach net-zero emissions by around mid-century, to curb warming to 1.5C.
Mr Johnson will be holding a press conference from Cop26 at 4.30pm this afternoon, according to reports in the Sun.
His climate change briefing is likely to be overshadowed by the recent row over MPs having second jobs, and allegations of Tory sleaze after MP Owen Paterson was saved from suspension and then later quit as an MP.
It has been claimed that former Cabinet minister Sir Geoffrey Cox “broke the rules” by using his parliamentary office for his second job offering legal advice.
The Times reported that the former attorney general, who has faced criticism over his outside earnings, used his Westminster office to participate remotely to advise the British Virgin Islands in a corruption probe launched by the Foreign Office.
Conservative MP and QC Sir Geoffrey has earned hundreds of thousands of pounds for his work with the islands, while allegations have surfaced that he was based in the Caribbean earlier this year while using lockdown proxy voting rules to continue to have his say in the Commons.
It comes after former environment secretary Mr Paterson announced he was quitting as MP for North Shropshire after 24 years, as an attempt by the government to delay punishment by ripping up the current standards system failed when opposition parties refused to offer their support.
Mr Johnson has been urged to apologise for his handling of the row.
Before heading back to Glasgow, the prime minister urged countries to “pull out all the stops” in the final few days on the Cop26 summit.
Negotiators are also trying to hammer out agreement on technical parts of the global climate treaty, the Paris Agreement, including common timeframes for national commitments on emissions reductions and agreed ways for countries to report on their progress, to help turn pledges into action.
There are also negotiations on providing finance for developing countries to cope with climate change and address the issue of loss and damage to people, livelihoods, land and infrastructure caused by global warming in poorer nations.
Mr Johnson said: “Negotiating teams are doing the hard yards in these final days of Cop26 to turn promises into action on climate change.
“There’s still much to do. Today I’ll be meeting with ministers and negotiators to hear about where progress has been made and where the gaps must be bridged.
“This is bigger than any one country and it is time for nations to put aside differences and come together for our planet and our people.
“We need to pull out all the stops if we’re going to keep 1.5C within our grasp.”
Alongside the negotiations, the Cop26 conference is marking 'transport day', with a number of aims drawn up, including that new heavy goods vehicles sold in the UK will need to be zero emissions by 2040.
Thirty countries have also agreed to work together to make zero emissions vehicles the new normal, and plans for “green shipping corridors” will be unveiled – facilitating a shift to zero emissions vessels.
Mr Johnson will be joined by UN Secretary General Antonio Guterres in Glasgow, where he will meet heads of delegations and other groups.
