BERLIN, July 11. /ITAR-TASS/. German Chancellor Angela Merkel has urged Ukrainian President Petro Poroshenko in a phone conversation on Thursday evening to use force proportionally against self-defense fighters in east Ukraine. Spokesperson for the German government Steffen Seibert reported this on Friday.

According to the spokesperson, the chancellor urged President Poroshenko to have a sense of proportion in the military operation against separatists and ensure the safety of civilians.

The German and Ukrainian leaders were unanimous in their opinion about the need to hold negotiations of a contact group with the participation of representatives of the self-defense forces to start implementing Poroshenko’s peaceful plan and establish truce from both sides, the German government’s spokesman said.

The press office of the Ukrainian president reported on Thursday that during their talk Poroshenko had informed the German chancellor about the current developments in the Donetsk Region.

Poroshenko spoke for the need to ensure a regime of monitoring and verification of a bilateral ceasefire and control over the border with Russia as well as “the immediate release of all captives and the start of political negotiations.”

In turn, Merkel said that representatives of the OSCE special monitoring mission had no access to border checkpoints due to the actions of self-defense fighters.

The Donetsk and Luhansk regions bordering Russia held referendums on May 11, in which most voters supported independence from Ukraine. South Ossetia has recognized the self-proclaimed Donetsk People's Republic and the Luhansk People's Republic. No other countries have followed suit so far.

Since mid-April, Kiev has been conducting a punitive operation against federalization supporters, which has already claimed hundreds of lives, destroyed buildings and forced tens of thousands to flee Ukraine.