World leaders are set to begin formal discussions Wednesday at the United Nations climate change conference in Turkey, seeking concrete measures to tackle global warming amid growing concerns that efforts to address the crisis remain inadequate and too slow.

However, the extent of progress that can be achieved at the Conference of the Parties, known as COP31, remains uncertain, with previous climate summits facing criticism over unfulfilled commitments and limited results.

At the 2023 conference in Dubai, delegates agreed to move away from fossil fuels, including coal, oil and gas, which are the main drivers of climate change. But subsequent conferences in Azerbaijan and Brazil failed to reach significant agreements on emissions reductions.

Last year's conference in Brazil ended with a compromise deal that pledged additional financial support to help climate-vulnerable countries adapt to the impacts of climate change.

This year's conference, hosted by Turkey with Australia leading the negotiations, officially opened on Monday amid mounting concerns that global efforts are falling short of what is needed to address the climate crisis.

Scientists warn that global temperatures are likely to exceed 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial levels recorded in the early 1800s. Keeping the rise within this limit was a key objective of the 2015 Paris Agreement and has remained central to international climate negotiations.

The discussions are also taking place against the backdrop of the war in Iran, which has driven up global prices of gasoline, oil and petroleum-based products, including fertilizers and pesticides. The price increases have prompted governments to reconsider their energy policies and investments in renewable sources such as wind and solar power.

"We don't need more promises, we need plans," said John Kerry, former US secretary of state and presidential climate envoy.

However, the United States, the world's second-largest polluter after China, is notably absent from the conference for the second consecutive year.

US President Donald Trump, who has dismissed climate change as a hoax, has targeted offshore wind energy projects and rolled back regulations aimed at limiting emissions from power plants.