This weekend marks a number of hotly anticipated first encounters between world leaders, but chief among them will be that of Trump and Russian President Vladimir Putin.

The pair’s first face-to-face meeting, due to take place on the summit’s sidelines on Friday morning, will be closely watched at a time when ties between the two countries have grown increasingly fraught after Russian interference in the U.S. election campaign and continued conflict in Syria.

The Kremlin said on Wednesday that the meeting would be used as an opportunity to establish an “effective working dialogue” between the two world leaders.

“This is the first meeting, the first time the two presidents will get acquainted – this is the main thing about it,” Kremlin spokesman Dmitry Peskov told a conference call with reporters.

“The expectation is that a working dialogue will be established, which is vitally important for the entire world when it comes to increasing the efficiency of resolving a critical mass of conflicts.”

The two premiers have so far had a tumultuous relationship. Trump said in April that U.S. relations with Russia were at an “all time low” after the countries came to a head over a missile strike in Syria. However, John Studzinski, vice chairman of The Blackstone Group, told CNBC Wednesday that the meeting could provide an opportunity for Trump to play to his strengths and warm hereto frosty relations between the two countries.

“Where he has one-on-one interactions, the way he’s had with many countries, like Japan for example, it does make a big difference,” Studzinski said.

However, the meeting is likely to be brief on details, and the Kremlin forewarned on Wednesday that it would unlikely allow time for Putin to fully outline his analysis of Ukraine, which has been in a state of crisis since the annexation of Crimea in 2014.

Trump is also due to meet with German Chancellor Angela Merkel on Thursday as part of a number of one-on-one meetings the German premier will hold with global leaders ahead of the summit. This will be the first time the two world leaders have met since a rather frosty encounter at the White House in March when Trump seemingly refused to shake Chancellor Merkel’s hand.