International benchmark Brent crude oil price increased by 0.38 percent to $55.45 while U.S. WTI rose 0.42 percent to $52.23 at 10.07 local time on Monday.
On early Friday, just after the U.S. military strikes on the Shayrat Airfield in central Syria, international benchmark Brent crude increased to $56.06, a 1.6 percent rise while American benchmark West Texas Intermediate rose 1.7 percent to $52.92.
Experts state that after the military operation against Syria, geopolitics became one of the big drivers in the oil markets.
According to Baker Hughes data revealed last week, U.S. oil drilling - for the 12th straight week counted 672 rigs, which is the highest since August 2015.
The number is expected to keep markets from breaking last week's one-month high of over $56 per barrel.
By Gulsen Cagatay