Brent crude futures were trading at $44.40 per barrel, up 13 cents, or 0.29%.

Analysts said that the price rise came on the back of renewed calls by some Opec members to freeze production in a bid to rein in output consistently outpacing demand.

"Opec members including Venezuela, Ecuador and Kuwait are said to be behind this latest reincarnation. But just like previous endeavours, it seems doomed to fail, given key Opec members (think: Saudi Arabia, Iraq, and Iran) persist in their battle for market share, ramping up exports apace," said Matt Smith of US-based ClipperData in a note.

Yet in the absence of an agreement, a fight for market share via high output and price discounts is still weighing on oil markets.

Iraq has dropped the September official selling price for Basra Light crude to Asia by $1.00 to minus $2.30 a barrel against the average of Oman/Dubai quotes from the previous month, the State Oil Marketing Organization said on Monday, making it the latest exporter to drop its prices.

Meanwhile, oil drilling in the In the US keeps increasing.

"Another increase in the rig count in the US also weighed on sentiment. The Baker Hughes data show rigs operating in the US are the highest since March (at 381)," ANZ bank said on Monday.

On the demand side, analysts at AB Bernstein said that oil demand growth had been strong in 2015 and the first half of this year, at 2.0% and 1.5% respectively, but that the outlook was weakening.

"In July following the UK Brexit vote, the IMF downgraded global growth by 10 basis points (bp) in 2016 and 20 bp in 2017. This has negative implications for (oil) demand," the analysts said.

"We expect that demand growth could slow in the second half of 2016 to around 1.1% and slow further in 2017 to a below consensus 1.0% on the current global growth outlook," AB Bernstein added.