Today's OPEC meeting should be "less contentious" than the protracted March session, the organisation's secretary general Mr Rilwanu Lukman said yesterday.

Mr Lukman dismissed as speculation analyst opinion that there was broad agreement to increase output by between 500,000 and one million barrels per day to stabilise rising oil prices.

"A number of people are jumping the gun. Until the ministers actually sit down and discuss and agree anything else is speculation."

However, asked whether the meeting would be less contentious than in March when Iran refused to sign up to an accord to increase production levels, Mr Lukman said: "It should be less contentious ... because we don't have the same problems we had in March."

Mr Lukman also stressed that Iran had ultimately backed the March agreement. On arrival in Vienna, Iranian Oil Minister Bijan Namdar Zangeneh refused to comment to reporters.

As uncertainly about the outcome of the Organisation of Petroleum and Exporting Countries' (OPEC) conference continued, prices levels firmed.

In London, benchmark Brent crude for August delivery climbed to $28.66 68 cents higher, while in New York, light sweet crude for July delivery rose to $32.17 a barrel, 48 cents higher.

In addition to agreeing to an output increase in an attempt to stabilise prices, the troubled March meeting informally agreed a price band mechanism, providing for an automatic output increase of 500,000 barrels a day if prices rose above an average of $28 a barrel.

OPEC subsequently failed to activate the mechanism.