European shares edged lower on Monday, as a sharp decline in financial stocks more than offset gains in the energy sector on concerns about political instability in top oil producer Russia.

The pan-European STOXX 600 index was down 0.3% by 0717 GMT, after posting its biggest weekly percentage loss in three months at the end of a central bank policy-packed week on Friday.

The energy sector, meanwhile, gained 0.2% as oil prices climbed after a revolt by Russian mercenaries over the weekend stoked concerns about a potential hit to oil supply from Russia.

The banking index was the biggest drag on the STOXX index, down 1%, with shares of Deutsche Bank falling 2.4%.

Reuters reported that Deutsche bank told clients it can no longer guarantee full access to Russian stocks that belong to them.

Market focus is also on a German business sentiment reading for June, due at 0800 GMT.