BERLIN (AP) — German Chancellor Angela Merkel on Wednesday prodded Russian President Vladimir Putin to do more to rein in rebels in Ukraine and renewed a threat of tougher sanctions if Moscow doesn’t change its behavior.

Merkel told German lawmakers before Wednesday’s Group of Seven summit that Russia must move from confrontation to cooperation, but said recent events paint “at best a mixed picture.”

Merkel said that Russia is key to deescalating the situation and efforts are underway to try to establish contact between Putin and Ukrainian President-elect Petro Poroshenko. She plans to meet Poroshenko in Berlin Thursday evening, the day before she meets Putin on the sidelines of events in France marking the 70th anniversary of the D-Day landings.

“It is really of decisive importance that President Putin exert his influence on the separatists to refrain from violence and intimidation, give up their weapons and end their occupations,” Merkel told Parliament.

The chancellor said that Russia is failing to prevent fighters and ammunition crossing its border, contributing to the continued destabilization of Ukraine.

“If this doesn’t stop, we will not shy away from imposing further sanctions,” she said, pointing to previous threats to move from targeted asset freezes and entry bans to wider economic sanctions.

However, she reiterated Germany’s longstanding insistence that “sanctions are not an end in themselves.”

“We do not want them. We want a close partnership with Russia,” she said. “But if they are unavoidable, then we will decide on them unanimously.”

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