Thanks to the COVID-19 vaccination campaign in the United States, Brent gained 0.6% and passed the $50 mark, and WTI gained 0.9% to $46.99.

Oil prices rose on Monday to their highest in 9 months, driven by the launch of vaccination in the United States against COVID-19, which gives hope for better days for the demand for black gold.

The barrel of North Sea Brent for delivery in February gained 0.6% or 32 cents in London from Friday's close at $50.29.

The US barrel of WTI for the month of January appreciated by 0.9% or 42 cents to 46.99 dollars.

The two benchmark contracts had not reached such a level since the beginning of March before the pandemic disrupted the US and global financial markets.

"Investors are confident that the vaccine (against COVID-19) will bring the situation back to normal and that demand for oil will accelerate," said Naeem Aslam of Avatrade.

The world's largest consumer of crude oil, the United States began a vast vaccination campaign against COVID-19 on Monday, after express preparations over the weekend.

Nearly three million doses are expected to be available by Wednesday, with the goal of vaccinating some 20 million Americans by the end of the year and 100 million by the end of March.

"There is no doubt that the deployment of the vaccine will have a positive effect on the demand for road fuel and, ultimately, aviation fuel," said Stephen Innes of Axi.

The analyst also attributed the rise in prices to the explosion of undetermined origin that hit an oil tanker off the Saudi city of Jeddah on Monday.

Saudi authorities did not immediately confirm the explosion off a key Red Sea port, which serves as a distribution center for Saudi oil giant Aramco.