The Swiss government says diplomat Heidi Tagliavini plans to step down as the Organization for Security and Cooperation in Europe's representative in talks between Moscow, Kiev and pro-Russian rebels in Ukraine.

Tagliavini, who previously worked on crises in places including Chechnya and Georgia, has played a low-key but well-regarded role for the past year in efforts to cool the conflict in eastern Ukraine.

The Swiss Foreign Ministry said Saturday that Tagliavini wants to give up her mandate soon. It gave no reason or exact timing for her departure.

The announcement comes four days after the latest talks ended with no visible results. The OSCE's deputy chief monitor in Ukraine has called for an urgent resumption of negotiations amid the worst fighting since a cease-fire began to take hold in March.