GLASGOW — British Prime Minister Boris Johnson is returning to the COP26 climate summit in Glasgow, urging nations to "pull out all the stops" to limit warming, BBC reported.

The first draft of an agreement setting out how countries will cut emissions to avoid temperature rises of above 1.5C has been published.

The agreement — or "cover decision" — sets out what negotiators hope will be the outcome of the COP26 talks.

It encourages richer countries to scale up support for poorer nations.

The seven-page draft agreement focuses on adaptation -- helping countries deal with the effects of climate change -- and finance, a controversial issue because poorer countries blame richer countries for not contributing enough.

The document says meeting the goal to limit global warming to 1.5C — which countries pledged to try to pursue under the Paris climate accord - needs meaningful and effective action in "this critical decade".

The agreement, which was published by the UK Cop26 presidency, will have to be negotiated and agreed by countries attending the talks.

Scientists have warned that keeping temperature rises to 1.5C -- beyond which the worst impacts of climate change will be felt -- requires global emissions to be cut by 45% by 2030 and to zero overall by mid-century.

With Wednesday named as transport day at COP26, the UK announced that new heavy goods vehicles sold from 2040 will need to have zero emissions.

Thirty countries have agreed to work together to increase the use of zero-emissions vehicles, while plans for "green shipping corridors" to help a shift towards zero-emissions vessels are also due to be unveiled.

Another 14 states which are responsible for more than 40% of global aviation emissions have committed to a new decarbonization target.

But the UK's Transport Secretary Grant Shapps said travel, including flying, should be "guilt-free" and said the government did not see aviation as "the ultimate evil".

He told the Daily Telegraph that changes to how we live our lives should not mean "the inability to go and visit you friends and family and do business".

Attendees at COP26, including the prime minister, have faced criticism for using planes for short journeys to and from the conference.