Secretary of State John Kerry meets with Russian President Vladimir Putin in Sochi on Tuesday, May 12, 2015. (Photo: The Kremlin)

(CNSNews.com) – Secretary of State John Kerry on Tuesday held out the prospect of an easing of sanctions against Moscow, using his first visit to Russia since the Ukraine crisis erupted to stress the importance of the two countries cooperating in the international arena.

At a joint press appearance with Foreign Minister Sergei Lavrov after hours of talks in Sochi, Kerry linked the removal of U.S. and European Union sanctions to full implementation of Ukraine ceasefire agreements negotiated in Minsk, Belarus last September and again in February.

“If and when Minsk is fully implemented, it is clear the U.S. and E.U. sanctions can begin to be rolled back,” he said.

Kerry made no mention in this regard of the situation in Crimea, whose annexation by Russia in March 2014 triggered the first punitive measures put in place by the U.S., including visa bans and asset freezes on senior Russian figures and sanctions against a key bank.

Crimea was not mentioned by either Kerry or Lavrov during the briefing. The U.S. maintains it does not recognize Russian control of the strategic peninsula, but the Minsk agreements of Sept. 2014 and Feb. 2015 focused on other areas of eastern Ukraine, with Crimea not addressed.

A year of fighting between Russian-backed separatists in the Donetsk and Luhansk regions in the east and the government in Kiev has cost more than 6,000 lives.

Russia’s intervention in the former Soviet republic sparked the worst crisis in U.S.-Russia relations since the end of the Cold War. Kerry’s visit, which included a meeting with President Vladimir Putin, was clearly intended as a fence-mending mission.

“We came here purposefully to have a very full and open dialogue with Russia’s leaders, the kind of dialogue that is absolutely essential in making progress on the many challenges that we face today,” Kerry said.

“And I am particularly grateful and I want to express my appreciation to President Putin for the very significant and serious conversation that he engaged in for the very significant amount of time that he committed to this discussion.”

Both Kerry and Lavrov spoke of the importance of Washington and Moscow working together to respond to international challenges.

“From the Geneva communique [an effort to end the Syrian civil war] to the removal of Syria’s chemical weapons, I would emphasize that we have seen what happens when Russia and the United States work together,” Kerry said. “It is clearly possible to make real progress and make important things happen.”

He pointed too to the Iran nuclear negotiations, where he said unity between the U.S., Russia and other P5+1 partners (Britain, France, China and Germany) “has been key to bringing us where we are today.”

“It is also going to be the key to completing a good [Iran nuclear] deal and to our being confident that that deal will be able to be well-implemented.”

Lavrov also called for cooperation between the two, adding that “resolution of many international problems really depends on our joint efforts – on the joint efforts of Russia and the U.S.”

Missiles to Iran not addressed

Although the two diplomats acknowledged persisting differences between the two governments over the causes of the conflict in Ukraine, Kerry appeared keen to play down a disagreement over another issue – Putin’s decision last month to lift a five year-old ban on the sale to Iran of S300 surface-to-air missiles, which could help to protect its nuclear facilities against future military strikes.

When a reporter asked Kerry if he had asked Lavrov to hold off the S300 sale, and asked Lavrov what his response had been, Lavrov replied, “I will make your life easy. He didn’t.”

Kerry then said that U.S. concerns about the S300 were known, but he added that the sale of such weaponry was not a violation of a relevant U.N. Security Council decision.

“So it’s not a question of any law or rule or judgment being broken; it’s a question of timing, in our judgment, as well as impact,” he said. “But we have already talked about it previously and we did not go into it today.”

During an earlier background briefing en route to Sochi, a senior State Department official was asked whether Kerry would ask the Russians to suspend or cancel the S300 sale.

“It’ll certainly come up, and we’ll talk to you about the conversation afterwards,” the official told reporters traveling with the secretary.

Asked whether the administration remains opposed to the sale, the official replied, “we’ve been clear that we oppose the sale of it, we’ve long opposed it, and our position on that hasn’t changed.”

As the S300 system is designed to protect military bases and infrastructure against attack by enemy aircraft, its deployment in Iran could impact on any potential military action in the future targeting Iran’s nuclear facilities.

Kerry’s mention of a U.N. Security Council resolution referred to resolution 1929 in 2010, which banned the sale to Iran of eight categories of conventional weapons.

Although one of those categories was “missiles or missile systems,” the measure contained a loophole, in that S300s are not listed on the U.N. Register of Conventional Arms.