"The Secretary General is also encouraged by the recent announcement by both India and China regarding their efforts to reduce their emissions through reduction in energy intensity," Janos Pasztor, Director of the Secretary General's Climate Change Support Team, told journalists here.
"This is a very positive step for a country where some 400 million people still do not have access to electricity," he added.
The UN official noted that China "has already embarked on an aggressive climate change plan." Brazil, South Africa, Indonesia, Mexico have announced ambitious carbon emission reduction plans ahead of the climate conference.
The Climate Change Conference slated to start this coming Monday at the Danish capital, where negotiators meet to chalk out a new climate treaty to replace the Kyoto Protocol which expires in 2012.
Three major players - the US, China and India - have made concrete commitments with Washington promising emission cuts of 17 per cent below 2005 levels by 2020 and 83 per cent by 2050, while Beijing has agreed to reduce its carbon intensity by 40 to 45 per cent compared to 2005 levels by 2020.
Ahead of the summit, the UN chief has reiterated that the US holds the key to a success at the Climate Conference.
"The Secretary General believes that the full engagement of the US in the multilateral process coupled with its recently announced international target and its own domestic effort on climate change is a potential game changer that can propel global action," Pasztor said.
Responding to concerns about the leaked emails which indicated UK scientists of exaggerating climate change threat, Pasztor said that top UN official Rajendra Pachauri had stated that it (emails) had not changed the majority of scientific opinion on the issue.
"What he has told us is that so far any information that has appeared – there may have been unfortunate developments - but nothing changes the sciences," he said, adding that majority of the scientific opinion has changed nothing.
In an interview with the BBC, Pachauri who is the chair of the Intergovernmental Panel on Climate Change, said "we will look into it in detail" and "we certainly don't want to brush anything under the carpet."
Pasztor told journalists that the leaked emails had not caused any practical damage in the flow of the negotiations.
The Copenhagen Conference will be the largest climate meet ever with over attendance of 15,000 people and more than 100 heads of state confirming their participation in the top-level talks.