Ministers carried on till 4 a.m. on Friday morning, and are expected to work into the night tonight.

Sources at the conference told edie that the most positive outcome likely would be an agreement on a deadline for reaching an agreement.

The Earth Negotiation Bulletin reported “table thumping and uncompromising exchanges” on Thursday night, with the US delegation saying that there was “no positive outcome guaranteed”.

On a more positive note, the USA has now signed the Convention, although there is still a majority in Congress that is opposed to ratification. Congress’ principal objection is to ratifying the convention without achieving binding commitments for greenhouse gas emissions reductions from developing countries.

There has been encouraging progress in this area, though, with both Argentina and Kazakhstan announcing voluntary commitments this week, and other developing nations expected to make similar announcements before the summit closes.

“Clinton’s signature hopefully demonstrates signs of leadership from the Americans,” said European Environment Commissioner, Ritt Bjerregaard. But, she added, this does need to be followed up with real actions.

UK Deputy Prime Minister, John Prescott, complained that progress in the talks had been slow, but said the main achievement was that people were now actually engaging in “real dialogue and real discussion”, including reaching compromises on key issues – instead of just turning up with lists of vetoes and conditions.

The area which has progressed furthest, says Prescott, is the Clean Development Mechanism (where developed countries gain credits by assisting developing countries with cleaner technology). This is the one issue that is being fast-tracked to ensure that it comes into action by the agreed deadline of April 2000. Prescott hopes the remaining issues will also be agreed upon by this date, but says this is far from certain.

For information on the final outcome of the summit, and live video recordings of the sessions, visit the COP IV website

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