French President Francois Hollande says he is heading to Ukraine with German Chancellor Angela Merkel to present a new peace initiative.

He said they will put forward the new plan before meeting Russian President Vladimir Putin in Moscow on Friday.

US Secretary of State John Kerry also landed in Kiev for talks on Thursday.

The diplomatic push to end the conflict, which has killed more than 5,000 people since last April, comes amid intensified fighting.

"Ukraine is at war. Heavy weapons are being used and civilians are being killed daily," Mr Hollande said at a news conference on Thursday.

He said the new peace proposal was based on the "territorial integrity" of Ukraine, which could be "acceptable to all".

A spokesman for the Kremlin confirmed that President Putin would meet with the two European leaders on Friday to discuss "the fastest possible end to the civil war in south eastern Ukraine".

Ukraine and the West have accused Russia of arming rebels in eastern Ukraine and sending regular troops across the border but Russia denies this.

Mr Kerry is in Kiev to hold talks with President Petro Poroshenko and Prime Minister Arseniy Yatsenyuk as the US considers whether to send weapons to help Ukraine fight the pro-Russian rebels.

The US has so far only provided "non-lethal" assistance to Ukraine.

But rather than arming Ukraine, Mr Hollande said there was another option: "That is the option of diplomacy - but that cannot go on indefinitely."