The price of oil has rebounded to just under $60 a barrel after its sharp fall at the end of last week.
Analysts said forecasts for another US cold spell hit Opec's plans to keep output at near full-throttle through the winter.
US crude rose 55 cents to $59.94 a barrel, recovering from its 2.1 per cent slide on Friday, while London Brent crude was up 69 cents to $58.00 a barrel.
Oil raced to its highest level in five weeks on Friday and natural gas set a second consecutive record-high as icy weather gripped the US Northeast and Midwest, driving up demand for heating fuels.
Profit-taking reversed those gains by Friday's close, but prospects for another cold snap at the weekend - after a period of more moderate weather - kept the market supported.
In Kuwait, Opec President Sheikh Ahmad al-Fahd al-Sabah said there was unanimous support to carry on pumping at the cartel's highest level for 25 years - about 30 million barrels daily.
Analysts said the market was also on edge after Sunday's explosions at the Buncefield depot in Hertfordshire, which has the capacity to hold 5 per cent of Britain's oil supply.