German Chancellor Angela Merkel says talks on climate change in a summit in Italy of the seven wealthy nations, known as the G7, were not successful as US President Donald Trump calls for more time to announce his position on the issue and whether Washington would remain committed to the landmark Paris Accord.

Merkel said on Saturday that Washington's partners in the G7 all remained in the dark about Trump’s intention on climate change, adding that the debate at the summit in Sicily was "very unsatisfactory."

"Here we have a situation of six against one, meaning there is still no sign of whether the US will remain in the Paris accord or not," Merkel said, adding, "The whole discussion on the topic of climate was very difficult, not to say very unsatisfactory."

The German chancellor, who spoke to reporters in Sicily after the summit, said the discussion on climate change was quite different than the one that happened on trade. She said the G7 member states clearly articulated that they would reject protectionism in trade policies. However, Merkel said the climate debate could not yield similar results as six governments agreed to endorse the Paris agreement but Trump tweeted that he will decide next week.

"I will make my final decision on the Paris Accord next week!" Trump tweeted.

The final declaration of the G7 summit also reflected the differences between the United States and other members on the issue.

"The United States of America is in the process of reviewing its policies on climate change and on the Paris Agreement and thus is not in a position to join the consensus on these topics," said the statement, adding that other members would “swiftly” begin to implement the Paris Agreement, which they said would be to the benefit of developing countries.

Trump had on several occasions during his presidential campaign criticized the accord, saying it could harm jobs inside the United States while being to the favor of countries such as China. The US president had even branded the agreement, which obliges parties to cut back on carbon emissions, a Chinese hoax. Like many other agreements signed under the administration of former US President Barack Obama, Trump has vowed that he would revise Washington's commitments under the deals to ensure US interests are protected.