SOCHI - US Secretary of State John Kerry said he had ‘frank’ talks about Ukraine, Syria and Iran with Russian President Vladimir Putin on Tuesday and said it was important to keep in contact.

With the United States and Russia on opposite sides of the conflicts in Ukraine and Syria, Kerry's trip appeared designed as much to maintain contact as anything else with U.S.-Russian relations at their lowest ebb since the Cold War. Kerry met Russian Foreign Minister Sergei Lavrov for more than four hours before he sat down with Putin in the Black Sea resort of Sochi in what was the highest-level U.S. visit to Russia since the Ukraine crisis began in the autumn of 2013.

‘Had frank discussions with President #Putin & FM #Lavrov on key issues including #IranTalks, #Syria, #Ukraine,’ Kerry said on his official Twitter feed. ‘Important to keep lines of communication between the U.S. and #Russia open as we address pressing global issues,’ he said. According to a Russian foreign ministry statement, Lavrov told Kerry: ‘Attempts to pressure us with sanctions is the way to (a) dead end.

‘Cooperation is only possible on the basis of fair and equal rights, without attempts to dictate and coerce.’ Ties between Washington and Moscow have deteriorated since Russia annexed Ukraine's Crimea Peninsula in March 2014 and backed pro-Russian separatist rebels in eastern Ukraine. Moscow accuses Washington of orchestrating last year's overthrow of a Ukrainian president who was supported by Russia.

The United States has accused Russia of failing to withdraw heavy equipment such as air defence systems, tanks and artillery from eastern Ukraine in violation of a peace plan agreed in February and known as Minsk 2. Russia denies Western and Ukrainian accusations that it is arming the pro-Russian separatists battling the government and supporting them with its own military forces. More than 6,100 people have been killed since April 2014 in the Ukraine crisis.

The United States and European Union imposed economic sanctions on Russia after it took over Crimea and have intensified them since. The U.S. official hinted they could be eased if Russia complied with the Minsk plan, which calls for withdrawing heavy weaponry and respecting Ukraine's border. Despite the strains, Putin smiled as he met Kerry. The U.S. secretary of state and the Russian foreign minister placed wreaths at a memorial to World War Two victims.

Russia's foreign ministry spokeswoman said Lavrov gave Kerry baskets of fresh tomatoes and potatoes, a possible allusion to Russia's decision last year to ban imports of European fruit and vegetables in response to Western sanctions.

He also presented Kerry with a T-shirt with ‘Victory’ and ‘1945-2015’, a reference to the 70th anniversary of victory over Nazi Germany. Western leaders boycotted Saturday's Moscow parade to mark the occasion because of its role in the Ukraine crisis. Kerry gave Lavrov a leather portfolio, US officials said. Washington and Moscow are also at odds over the civil war in Syria, where Russia has backed Syrian President Bashar al-Assad while the United States wants a political transition to end his family's 45-year-old rule. While there have been no outward signs of a Russian reversal on Syria, U.S. officials hope recent defeats to Assad's forces may change the Russian stance. Insurgents overran the northwestern Syrian town of Jisr al Shughour last month and the provincial city of Idlib a month earlier, both in the rich agricultural province of Idlib.