The second commitment period of the Kyoto Protocol, the international accord to cut greenhouse gas emission, is facing uncertainty as the fourth round of climate talks draw to a close in Tianjin, China, Saturday.

"As of today, we are not yet close to making a final decision on the second commitment period. There is still some work to be done on that," said John Ashe, chairman of the Kyoto Protocol negotiating group in an exclusive interview with Xinhua Friday.

The Kyoto Protocol, which initially came into force in 2005, legally obliges more than 40 developed countries and European Union to reduce their greenhouse-gas emissions.

It stipulates that developed countries should cut their emissions by 5.2 percent on average from 1990 levels in the first commitment period from 2008 to 2012.

The goal was expected to be achieved before the deadline on Dec. 31, 2012, said Ashe.

However, the second commitment had not yet made any progress.

"The complex process we're involved in, it is never smooth, it is never easy. But it has largely been uneventful, that is also a good sign," he said.

Although most developed countries had made pledges, negotiations on the second commitment period were slow and hard.

Different groups of countries faced "fundamental" disputes, because they all had their own worries on the problems of green-gas emissions reduction, capital and techniques.

Some developed countries even hoped to abolish or amend the Protocol, saying developing countries should share the same responsibilities.

Only Norway had made a clear commitment to a 30-percent cut in greenhouse-gas emissions.

"We are not sure that there will be a second commitment period, although no one has come out to say that there ought not to be or there will definitely not be a second commitment period," said Ashe.

"We are in a sort of grey area."

The talks in Tianjin from Oct. 4 to 9 are the last preparatory session before the Cancun summit, which is to be held in Cancun, Mexico, at the end of this year.

Three other preparatory talks were held in Bonn, Germany.