Lars Lokke Rasmussen, the Danish prime minister, is set to replace the president of the UN climate talks in time for the final summit session in Copenhagen.
Connie Hedegaard, the Danish minister who was heading talks, resigned on Wednesday in a move she said was simply procedural.
"With so many heads of state and government having arrived, it's appropriate that the prime minister of Denmark presides," Hedegaard told the 193-nation meeting.
"However, the prime minister has appointed me as his special representative and I will thus continue to negotiate the ... outcome with my colleagues," she said.
Alan Fisher, Al Jazeera's correspondent at the summit, said the move was always planned.
"There is no suggestion behind the scenes that there is any frustration, on Connie Hedegaard's part, of a failure to reach some sort of draft agreement here," Fisher said.
"There's no question that the Danish government is even concerned about Hedegaard, and the way she's conducted proceedings here."
The announcement came the same day that Danish police detained at least 100 protesters in the country's capital, for attempting to break into the UN conference, where representatives are negotiating a new global warming deal.
World leaders have begun arriving at the 12-day talks as they enter their final stretch.
Barack Obama, the US president, and Wen Jiabao, the Chinese prime minister, are expected to arrive in the last few days of talks.