BERLIN (Reuters) - Expanding the number of countries involved in Russian-backed peace talks for Syria could offer a chance to jumpstart negotiations on a political solution, Germany’s top official for Russia policy said in an interview published on Tuesday.

German Chancellor Angela Merkel welcomes Russian President Vladimir Putin for talks on a stalled peace plan for eastern Ukraine at the chancellery in Berlin, Germany, October 19, 2016. REUTERS/Hannibal Hanschke

Gernot Erler suggested that German Chancellor Angela Merkel could raise the issue with Russian President Vladimir Putin when they meet in Sochi, Russia later on Tuesday.

“We have to acknowledge that all previous peace efforts have failed,” Erler told the Berliner Zeitung newspaper, noting that neither the U.N. initiative led by diplomat Staffan de Mistura nor the Russia-brokered ceasefire had led to tangible results.

“As a result we have to think of something new. I think the German side should ask Putin if he can imagine including more countries in the negotiations. That could offer an opportunity to at least organize a negotiating process,” he said.

He said it was clear that a solution to ending the war in Syria was now unthinkable without the participation of Russia, whose military intervention has shifted the course of the six-year-old war in favor of its ally, President Bashar al-Assad.

Russian Foreign Minister Sergei Lavrov told news agencies on Saturday that Moscow was ready to cooperate with the United States on settling the Syrian crisis.

Interfax also quoted Lavrov’s deputy, Mikhail Bogdanov, as saying the armed Syrian opposition would participate in the next round of Russian-backed peace talks in Kazakhstan’s capital Astana on May 3-4, which will also involve Iran and Turkey.

Erler rejected a suggestion by Jordan’s King Abdullah that the West should accept Russia’s 2014 annexation of the Crimea region of Ukraine and stop criticizing Moscow to encourage Putin to drop his support for Assad.

“I consider that a dubious idea. It would mix up two issues that have nothing to do with each other,” Erler said.

He said U.S. President Donald Trump initially appeared to favor such a “deal” but had since realized that foreign policy crises could not be handled like real estate transactions.

Russia has vetoed eight resolutions on Syria to shield Assad’s government from action, most recently blocking condemnation of a chemical weapons attack last month that killed dozens of people, including many children. China has backed Russia and vetoed six resolutions.

Erler said Merkel would also press Moscow to uphold its written commitments under the Minsk peace process aimed at ending the violence in eastern Ukraine.

He said Merkel would assure Putin that sanctions against Moscow could be lifted quickly if Moscow demonstrated its resolve to implement the Minsk agreement.

“But Moscow has known that for some time, so the ability to add pressure is very limited,” he said.