German Foreign Minister Frank-Walter Steinmeier says Ukrainian leaders have agreed to observe a new cease-fire for the country's east.

Steinmeier was speaking in Kyiv on September 14 at a joint press conference with his French and Ukrainian counterparts, Jean-Marc Ayrault and Pavlo Klimkin, following talks with President Petro Poroshenko.

"We came with a promise from Moscow that effective [September 15] there will be a truce that will last at least a week," Steinmeier also said, a day after the leaders of the Russia-backed separatists in the Donetsk and Luhansk regions declared a unilateral cease-fire.

The sides earlier agreed to abide by a truce to coincide with the start of the school year on September 1, but it failed to stop the fighting between government forces and separatists that has killed more than 9,500 people since April 2014.

Ayrault urged the Ukrainian leadership to commit themselves more fully to the February 2015 Minsk agreement brokered by Berlin and Paris, saying, "There is no Plan B."

The peace plan envisages holding elections in separatist-held areas and partial autonomy for the country's eastern regions.

Klimkin said an agreement with Russia over "the sequence of steps and guarantees" for implementing the peace terms was needed.

Based on reporting by AP, Reuters, dpa, and AFP