Norway hopes that nations will strike agreements on reforestation during the upcoming Cancun climate change talks, the nation's ambassador to Mexico Arne Aasheim told Xinhua on Tuesday.

"A legally binding treaty should be the goal, but it is a process that will take time," Aasheim said, adding that he does not think that a binding accord will be reached during the talks.

"Some 17 percent of emissions are caused by deforestation. We have experience and it is an area where we want to make commitments with nations. The forests act as the world's lungs," Aasheim said.

Norway has raised its tree coverage to 28 percent from 25 percent earlier, but cold and altitude hamper further efforts as the trees that withstand the nation's chilly climate cannot cope with its altitude.

"It is hard to increase much beyond 28 percent because much of Norway is more than 700 meters above sea level," Aasheim said.

"We are doing what we can domestically and investing in other nations. We have invested more than $1 billion in Mexico, Guyana, the Democratic Republic of Congo, Indonesia and Brazil. We are investing in those nations to halt deforestation," he added.

Norway has cooperated with Mexico in reforestation and also in helping reduce the emission and burning of natural gas at Petroleos Mexicanos (Pemex), the nation's state-owned oil producer.

"In Norway we already have more gas than oil production. Norway is going to have more gas than oil for some time and is trying to use it to replace coal," he said. As a result, Pemex's Norwegian counterpart Statoil, which is 75 percent state owned, has developed a range of techniques for capturing and using natural gas.

The two firms began working together in 2004, according to an article published on Norwegian embassy's website. The firms' pilot project, at the Tres Hermanos in Gulf Coast state Veracruz, will reduce carbon dioxide emissions by 83,000 tons over 10 years, drawing in money via the United Nations' Clean Development Mechanism, part of the Kyoto climate change protocol.

Aasheim praised the efforts made by Mexico to create trust and reach agreements during the run-up to the 16th Conference of the Parties of the United Nations Framework Convention on Climate Change (COP16).

He was also impressed by another agreement recently signed by 140 mayors in Mexico City to tackle greenhouse gas emissions and boost energy efficiency and renewable fuel use.

"Cities and local authorities can make a real difference because some 80 percent of greenhouse gases come from urban areas," he said.

In Norway's capital Oslo, "authorities have managed to reduce consumption of power using efficiency measures, including increasing public transport to reduce the use of cars, which is something that could apply to many cities," he added.

"All nations should contribute although industrialized nations have a special responsibility," he said.