These sticking points were supposed to be resolved during a session on Wednesday. But just minutes into the meeting, Andre Corrêa do Lago, the diplomat presiding over the talks, announced that more consultations were needed and pushed the deadline to Saturday.

Countries "have engaged in open and honest discussions," he said, but "they need more time."

"The scenario in which it was potentially going to be passed on to the ministers in the second week seems to be confirmed," a source told AFP following the discussions.

It is customary for political leaders to arrive during the second and final week of UN climate talks to finalize the agreements drafted by negotiators in the opening days.

The Brazilian presidency managed to secure the inclusion of several key items on the agenda Monday, while promising consultations on more contentious points raised by various country groups.

The Alliance of Small Island States (AOSIS), supported by others, wants the summit to officially address underwhelming emissions-cutting commitments, which have made overshooting the 1.5C warming threshold set by the Paris agreement virtually certain.

Another major issue, raised by a coalition of developing nations, concerns the financial support that wealthier countries are obligated to provide. A further point of contention involves "unilateral" trade measures -- such as the European carbon border tax -- criticized by Global South countries including India and China.

To find common ground, Brazil is banking on its close ties with Beijing, New Delhi, and other major developing nations.

"This greatly facilitates our capacity for dialogue," Mauricio Lyrio, Brazil's chief negotiator, told AFP. "What we have noticed is a political will from everyone to help Brazil have a successful COP."