Oil producers were last night negotiating new output restraint measures aimed at propping up oil prices hurt by a global economic downturn.

Faced with evidence that world demand for the cartel's exports is faltering, the group is considering cutting between 750,000 and one million barrels daily.

"It's in that range. There's more or less a consensus in that range," said Venezuelan oil minister Mr Alvaro Silva.

Gathering for today's conference, ministers have had their calculations complicated by gloomy demand forecasts, a two-day price slide and the slump on world equity markets.

Fallout from economic deterioration in the US has hit the cartel's main growth markets in Asia and there are fears that slowing petroleum consumption could send prices into a tailspin.

Concern has grown among the producers, responsible for 60 per cent of world oil exports, that prices might be on the verge of a collapse as spreading economic woes compound the seasonal decline in demand at the tail end of winter.