Countries have been working through the night on 11th hour negotiations to secure a new international climate change agreement.
Ministers from more than 190 countries have continued trying to find compromises to land the deal at the United Nations summit in Paris as the talks slipped past their official Friday evening deadline.
Countries have been engaged in "shuttle diplomacy" between groups to find common ground.
And US president Barack Obama has been calling fellow leaders in recent days, with a phone conversation to president Xi Jinping of China as the talks reached the end game, in the push to achieve an ambitious climate deal.
The French organisers of the conference are planning to bring out a final draft of the text this morning, with hopes the agreement can be gavelled through this afternoon - though seasoned observers believe there are many hours to go before the end of the talks.
The final deal could include references to making efforts to keep temperature rises to no more than 1.5C above pre-industrial levels - a key ask of the most vulnerable countries who fear greater warming could threaten their very survival - as many countries are thought to be "comfortable" with the idea.
But the level of ambition in the final deal remains one of the key issues, according to French foreign minister Laurent Fabius, who is chairing the talks which he said have almost reached the "end of the road".
The issue of "loss and damage" - the recognition that some of the most vulnerable countries need support to cope with irreversible impacts such as inundation of their land from rising sea levels - is also hugely difficult, with developed countries refusing anything that could open them up to liability or compensation.
Finance for poor countries to deal with climate change and the different responsibilities of developed and developing countries to tackle climate change and pay for it, are also still the focus of political dispute.
As the talks headed past the deadline, tensions began to show with Indian environment minister Prakash Javadekar accusing developed countries of not showing flexibility towards poorer countries.
And Marshall Islands foreign minister Tony de Brum, the driving force behind the "high ambition coalition" of countries including the EU calling for a strong deal at the talks, warned there had been a "co-ordinated campaign to gut the text" of ambition by some countries.
The coalition is calling for a robust five-yearly review system which would see countries review and increase their pledged emissions cuts, a move that is necessary as current climate action plans would only limit temperature rises to 2.7C.
It is thought there is movement on issues, however, that could lead to compromises, and that all countries still want to get a deal.