A group of world leaders called Monday for countries around the world to put a price on carbon to strengthen the international fight against climate change.

As a week of talks on a global climate agreement opened in Bonn, the leaders of the World Bank, International Monetary Fund, Germany, France, Chile, Mexico, Ethiopia, and the Philippines called on others to back pricing schemes "to steer the global economy towards a low-carbon, productive, competitive future without the dangerous levels of carbon pollution driving warming."

The group, known as the Carbon Pricing Panel, said in a statement that carbon pricing creates a basis for private companies to "make long-term investments in climate-smart development."

So far, they said, about 40 nations and 23 cities, states and regions have initiated carbon-pricing schemes.

But without a very wide implementation of such schemes, the playing field for investment and trade remains uneven and unfair.

The panel also includes California Governor Jerry Brown, Rio de Janeiro Mayor Eduardo Paes, and leading companies and financial groups including California's CalPERS, ENGIE of France, India's Mahindra Group, and Netherlands-based Royal DSM.

"Low-carbon technologies are an element in the fight against worldwide climate change. With a price for carbon and a global carbon market, we promote investment in these climate-friendly technologies," said Merkel in the statement.

"There has never been a global movement to put a price on carbon at this level and with this degree of unison," said World Bank President Jim Yong Kim.

"It marks a turning point from the debate on the economic systems needed for low carbon growth to the implementation of policies and pricing mechanisms to deliver jobs, clean growth and prosperity," he said.

The call came as negotiators in Bonn began a final round of talks to map out a global agreement that could be finalized at the 195-nation United Nations climate conference in Paris on November 30-December 11.

Due to take effect in 2020, the UN climate pact would be the first signed by virtually all the world's nations.

The overarching goal is to limit average global warming to two degrees Celsius (3.6 degrees Fahrenheit) over pre-Industrial Revolution levels -- beyond which scientists say the impacts will be disastrous.