Russian President Vladimir Putin met with U.S. President Barack Obama on the sidelines of the Group of 20 (G-20) summit in China, continuing a series of meetings with high-profile leaders and signaling a rapprochement between Russia and the West.

Putin and Obama discussed Syria and Ukraine when they met on Monday, Kremlin spokesman Dmitry Peskov told reporters at the meeting in Hangzhou, according to Russia's TASS news agency. Asked about the mood at the meeting, Peskov reportedly said that "it went well. Work will continue."

The chat had a "businesslike tone" and went on longer than anticipated, a senior U.S. administration official said, according to Reuters. Obama later confirmed that he had productive concentrations on what a real cessation of hostilities in Syria would look like and made clear that sanctions on Russia would remain until the the Minsk cease-fire agreement was implemented.

The subjects of Syria and Ukraine have been points of contention between Russia and the West for a number of years now. Russia is part of an awkward alliance attempting to defeat the terrorist group known as Islamic State in Syria and Iraq.

Russia has been criticized for its military action seemingly aimed at keeping Syrian President Bashar al-Assad's controversial regime in power, however, although the West has tried to persuade Putin to use his influence on Assad to try to find a peaceful solution to the ongoing civil war in the country.

Uncomfortably, Russia's alliance with the West over Syria comes at a time when it is simultaneously under international sanctions for its annexation of Crimea in Ukraine, as well as its alleged role in a pro-Russian uprising in eastern Ukraine, which have both isolated the country economically and politically.

Yet Putin has held several high-profile meetings with Western leaders in the last few weeks – not least of all at the G-20 meeting in China where he has already held talks with U.K. Prime Minister Theresa May, signaling that the strongman leader and Russia could be "coming in from the cold" on a diplomatic level.

Putin has already met Chinese President Xi Jinping and Turkish President Recep Tayyip Erdogan (again, after a political rapprochement) shortly before, and at, the G-20 summit as well as holding other meetings with global leaders at the Eastern Economic Forum held in the Russian city of Vladivostok on Friday and Saturday.

Continuing a busy weekend, Putin was in the front row of G-20 family photo in China on Sunday, standing between Turkey's Erdogan and French President Francois Hollande. Analysts were quick to pick up on Putin's presence and his busy schedule at the summit.