Oil prices increased on Monday following a weekend uprising by Russian mercenaries that sparked worries about political unrest in that country and possible effects on oil supplies from one of the biggest producers in the world.

Brent crude futures added 27 cents at $74.12 per barrel meanwhile WTI rose 28 cents at $69.44 per barrel. Both added 0.4%.

There are worries that Putin would impose martial law, barring workers from reporting to important loading ports and energy facilities, potentially blocking millions of barrels of exports, according to RBC Capital Markets analyst Helima Croft.

Both Brent and WTI decreased by about 3.6% last week due to concerns that further interest rate increases by the U.S. Federal Reserve might reduce demand for oil at a time when investors have also been let down by China's economic recovery as a result of several months of weaker-than-anticipated consumption, production, and real estate market data.