German President Joachim Gauck has opened an annual security conference in Munich with a call for Germany to play a greater role on the world stage.
Gauck said that "Germany should engage as a good partner earlier, more decisively and more substantially" in world crises.
He was responding to criticism that Germany, despite having the European Union's largest economy, has long followed a policy of "military restraint" and limited its contributions to international peacekeeping missions.
The agenda of this year's three-day Munich Security Conference is expected to include the war in Syria, the crisis in Ukraine, Iran's nuclear program, and U.S. surveillance operations.
Some 20 heads of state and government, together with dozens of foreign and defense ministers, are in Munich for the start of the event.
Washington’s delegates include Secretary of State John Kerry and Defense Secretary Chuck Hagel.
Russian media reports said Lavrov and Kerry might meet for talks on the sidelines of the event.
Also attending are UN Secretary-General Ban Ki-moon, EU Foreign Policy Chief Catherine Ashton, European Commission President Herman Van Rompuy, NATO Secretary-General Anders Fogh Rasmussen, and Syria international envoy Lakhdar Brahimi.
Kerry was planning to meet Ukrainian opposition leaders Vitali Klitschko and Arseniy Yatsenyuk on the sidelines of the conference, while Lavrov meets Zarif and Ukraine’s acting Foreign Minister Leonid Kozhara.
Klitschko is also expected to address the event.
Based on reporting by RFE/RL correspondent Charles Recknagel and reports by Reuters, AP, AFP, Itar-Tass, and Interfax