Brent crude for November delivery gained 2.8 percent to $107.54 a barrel, while US benchmark West Texas Intermediate for October rose 2.3 percent to $102.34.

Both contracts extended last week's gains after climbing back above the $100 threshold.

The market's focus remained firmly on the Middle East, where fresh security concerns threatened key export routes.

It came as Saudi Arabia temporarily shut its East-West pipeline following drone attacks, while a merchant vessel was struck in the Strait of Hormuz on Sunday killing one person and injuring three others, Iranian authorities said.

The strait was free to transit before the war, but Iran now requires vessels to obtain permission and is considering a mechanism to impose service fees.

Ships that do not comply are regularly targeted by Iranian strikes, while the United States periodically bombs the Iranian coastline to challenge the Islamic republic's control of the strait.

Oman has also postponed talks between Iran and Gulf states on the future of the strategic waterway, a vital route for a large share of the world's seaborne oil trade.