"Even without the election question, the meeting between Trump and Putin is key for the future of Europe and the Middle East. The question of U.S. sanctions against Russia for its incursion into Crimea, the future of Syria after the impending fall of ISIS and how to prevent American and Russian forces active in the country from clashing, and willingness of the US to stand by NATO allies are all in the balance," CNN reported.

Read alsoPutin adds occupied Crimea's inland waters to free economic zone to boost investmentAs UNIAN reported earlier, Trump will convene a high-stakes meeting with Putin at the summit of industrial and emerging-market nations in Germany amid swirling allegations about Moscow's role in the 2016 elections, the White House said.

The summit will be hosted by Hamburg on July 7-8.