Oil prices have increased as the market signalled optimism over potential action by Organisation of the Petroleum Exporting Countries (OPEC) members to freeze output in order to sustain the market.

Brent crude futures were up 24 cents at $48.59 per barrel, while the US West Texas Intermediate crude rose 24 cents and reached $46.16 per barrel, Reuters reported.

Oil prices have gained support due to loss of production in Nigeria following militant attacks and pipeline problems.

Much of the gains have been primarily due to investor optimism that oil producers are expected to take action to rein in increasing supply.

"After Saudi Energy Minister Khalid al-Falih said that the country plans to discuss with others to stabilise oil markets, the hopes further increased."

After Saudi Energy Minister Khalid al-Falih said that the country plans to discuss with others to stabilise oil markets, the hopes further increased.

Dominic Haywood of Energy Aspects told the news agency: "August and September, from a fundamental perspective, look strong."

Venezuela is struggling with an economic and political crisis and is on track for a fall in oil output in 14 years annually.

In the 12 months to June, crude output in the country declined 9% to 2.36 million barrels per day.