Gordon Brown has maintained the government's pressure on oil cartel Opec to step up production in a bid to ease soaring prices.

The chancellor has also indicated that he could scrap plans to increase fuel duty this autumn.

"Once I see the progress that is being made by Opec in raising production and getting the oil price under control I'll review the situation in August," he told the BBC.

"I want the focus of the next few weeks to be on where the source really lies, and the source of the problem is inadequate production and the instability in the Middle East."

His comments came after Opec agreed to lift oil production, but by a smaller amount than many experts had expected.

Production will rise by two million barrels a day from July 1, with a further 500,000 barrels added from the start of August.

Prices on the international markets eased slightly following the announcement.