Washington DC - US climate envoy John Kerry hit back Thursday at claims that he uses a carbon-spewing private jet as he was grilled by Republican lawmakers on the State Department's environmental agenda ahead of a trip to China.

Kerry, who will fly to Beijing for talks on emission reduction over the weekend, said he had largely used commercial airliners in his work in President Joe Biden's administration and recalled no flights on private aircraft in that time.

Kerry, a former secretary of state who has long been a target of Republicans, appeared irritated by Florida congressman Cory Mills saying he hoped "it wasn't too problematic for your operational team and your private jet to get here."

"I just don't agree with your facts, which began with the presentation of one of the most outrageously persistent lies that I hear, which is this private jet," Kerry told the Republican-led House Foreign Affairs Committee's oversight panel.

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"We don't own a private jet. I don't own a private jet. I personally have never owned a private jet. And obviously it's pretty stupid to talk about coming in a private jet from the State Department up here."

During the same heated hearing, Kerry was asked whether the US would financially contribute to a fund that would pay countries that have been damaged by climate-driven disasters, to which he replied: "No, under no circumstances."

Kerry's critics have slammed his use of a Gulfstream GIV-SP chartered from his wife's company that made 48 trips during the Biden administration, according to Fox News, before it was sold last year.

The United States and China are the world's largest emitters of greenhouse gases as well as some of the world's biggest investors in renewable energy.

Kerry follows in the footsteps of Secretary of State Antony Blinken, who last month paid the highest-ranking US visit to Beijing in nearly five years, and Treasury Secretary Janet Yellen who was in China last week.