The US says it will contribute to a fund to help developing countries deal with climate change. But at the same time, the country's climate negotiator claims Washington does not see the need to make "reparations" for decades of carbon pollution.

The US has rejected claims it has a carbon debt to pay to other nations.

The country's lead climate negotiator made the remarks at the Copenhagen talks on Wednesday.

Todd Stern, US Negotiator Copenhagen Climate Change, said, "We absolutely recognize our historic role in putting the emissions in the atmosphere up there, that are there now. But the sense of guilt or culpability or reparations, I categorically reject that."

Stern says both developed and developing countries should share the responsibility to solve the climate change issue.

He says he is prepared to work to reach a deal in Copenhagen, including offering cash injections to help poor nations.

Meanwhile, the US Environmental Protection Agency stressed the country's greenhouse gases should be regulated.

On Monday, the agency delivered a ruling stating that greenhouse gases endanger human health. This enables the agency to regulate gases without the approval of Congress.

Lisa Jackson, Administrator of EU Emvironmental Protection Agency, said, "We're not at either/or. We need legislation. We desperately need it so that the economy and business gives a strong signal once and for all that clean energy is the profitable energy."

Meanwhile, other nations at the Copenhagen talks have called on the US to boost its efforts to cut emissions.

The US current offer is to reduce emissions by around 17 percent by 2020, from 2005 levels. This is only a 3 percent cut from 1990 levels.