The oil price slid around 10% on Monday as the US and Iran halted strikes and Oman led diplomatic efforts to once again resume safe passage for ships through the Strait of Hormuz.
Brent crude topped $100 at the tail end of last week, but reached a low on Monday of $87.64 before settling around $90.
The change was triggered by fresh hopes of an end to the Middle East conflict, with both the US and Iran suspending fighting.
On Sunday, the US ambassador the United Nations, Mike Waltz, told reporters Donald Trump had opted to pause military strikes on Iran in order to allow room for talks between the parties.
Iran reportedly agreed to suspend strikes as well as long as the US did the same.
The Times reports Iranian officials said negotiations had been "fruitful", with "some progress" made.