MOSCOW (AFP) - US Secretary of State John Kerry met President Vladimir Putin at the Kremlin on Thursday to try to convince him to support an end to Bashar al-Assad's rule in Syria.
Putin had warm words for Kerry at the start of their meeting, thanking him for his "business-like" approach and hailing the United States for helping broker a ceasefire in the war-torn country.
"We understand that what we have managed to achieve on Syria has only been possible thanks to the constructive position of the political leadership in the US, the position of President Obama," Putin said.
Kerry lauded the truce between government forces and the opposition that has seen fighting drop and called to "make progress even deeper" towards finding a lasting political solution to the conflict.
"It's fair to say, Mr President, that the serious approach with which we have been able to cooperate with one another has made a difference for the lives of the people of Syria," Kerry said.
"You have ideas and you have made a very critical decision with respect to the drawdown of your forces," Kerry said, referring to Putin's partial withdrawal of Russian forces he had sent to prop up Assad's regime.
"We, obviously, also have some ideas about how we can together, most effectively, make progress even deeper and the begin the very serious political process of transition."
Earlier, Kerry had met his Russian counterpart Foreign Minister Sergei Lavrov and told him the bomb attacks in Brussels demonstrated that countries must come together.
"Our counterparts, whom you and I have both talked to in the last days, are hopeful that these meetings here in Moscow today have an ability to be able to further define and chart the road ahead so that we can bring this conflict in Syria to a close as fast as possible," Kerry said.
Lavrov told Kerry diplomatic efforts had been focused on creating a "balance of interests" among all sides involved in the Syrian crisis, including Moscow and Washington.
But US officials fear the Syrian opposition will drop out of UN-mediated peace talks in Geneva unless Russia's ally Assad agrees to step down as part of a political transition.
Putin has stood by Assad, and even sent Russian warplanes to fight to protect his regime and strike the extremist Islamic State in Iraq and Syria (ISIS) group, which has seized territory in the east of the country.
But Moscow's partial withdrawal of its forces from Syria has created what Washington believes is an opportunity to press for a change of stance on the regime.
"What we're looking for, and what we've been looking for, for a long time is how are we going to transition away from Assad's leadership," a senior US official told reporters.
In Geneva, opposition negotiators confirmed that they are counting on Russia to keep the pressure on the regime.
After the latest round of meetings with UN mediator Staffan de Mistura, opposition spokesman Bassma Kodmani told journalists: "This is a unique moment, a precious moment and we hope Russia will seize this moment and use its leverage."
And de Mistura said on Thursday that the UN was aiming to restart Syria peace talks on April 9.
In a sign of Russia's strengthened role as a Middle East powerbroker, both Kerry and Putin met separately with the Crown Prince of Abu Dhabi, Mohammed bin Zayed al-Nahyan.
Kerry's visit also comes while Europe faces a security crisis after Tuesday's attacks in Brussels, which left 31 dead and 300 injured.
On Wednesday, Lavrov called for Europe to drop its "geopolitical games" and unite behind efforts to fight terrorism, as Russia continues its air strikes in Syria.
Kerry acknowledged that the ceasefire negotiated by Russia and the United States between Assad and the armed Syrian opposition has led to a steep reduction in violence, but that much work lay ahead.
"We both know that more needs to be done in terms of both the reduction of violence and the flow of humanitarian goods," Kerry told Lavrov.
Kerry will next travel to Brussels to offer Washington's support for Belgium and Europe's efforts to counter violent extremism.