BERLIN (Reuters) - German Foreign Minister Frank-Walter Steinmeier urged world leaders on Sunday to work to calm the crisis in Ukraine and defended Russia's membership of the Group of Eight leading economies, which enabled the West to talk directly with Moscow.

"The format of the G8 is actually the only one in which we in the West can speak directly with Russia," he told the public broadcaster ARD. "Should we really give up this unique format?"

U.S. Secretary of State John Kerry earlier said recent events had "put at question Russia's capacity to be within the G8", which Russia joined in 1998.

Steinmeier said too much focus on possible aggravations of the situation could actually help to bring them about.

He urged Ukraine and Russia to talk with one another, if necessary through intermediaries.

Steinmeier once again urged Russia to avoid escalating the crisis and to send its troops back to their barracks. "It is a very dangerous situation there."

Germany is heavily dependent on Russia for its natural gas needs, and is the biggest export market of Russia's state-controlled gas producer Gazprom.

Ignoring warnings from Western leaders, Russian President Vladimir Putin won permission from his parliament on Saturday to use military force in Ukraine. The stated purpose was to protect Russian citizens in Ukraine following the overthrow of Russian-backed president Viktor Yanukovich a week ago.

Russian forces have already bloodlessly seized Crimea - a Black Sea peninsula with a majority of Russian speakers where Moscow has a major naval base.

(Reporting by Thorsten Severin; Writing by Sarah Marsh; Editing by Kevin Liffey)