Protecting the interests of developing nations on the issue of climate change was at centre of the discussions as the ministers from Brazil, South Africa, India and China (BASIC) gathered in Durban.
The meeting held at the weekend came in the run up to the United Nations Conference on Climate Change to be held in Durban in November and December this year.
"Ministers re-emphasised that an agreement on the second commitment period of the Kyoto Protocol is absolutely critical for the success of the Durban Conference... The ministers reaffirmed the commitment of BASIC countries to continue working to strengthen the unity of G77," they said.
The first commitment period to the Kyoto Protocol ends in 2012, and there is not agreement yet on how the protocol will be taken forward.
Some western nations are clearly opposed to a second commitment period unless developing countries too agree to greater commitments.
The UN meeting in Copenhagen in 2009 had failed to undo the differences between the developed and the developing economies on the issue of commitments.
The group called for unilateral approaches, like inclusion of emissions from aviation sector in EU Emissions Trading Scheme or establishing unilateral carbon accounting rules, Bua news said.