US President Trump has opened up on his recent phone calls with Putin and Zelensky, with the former leaving him feeling 'very disappointed'

"We're going to send some more weapons – we have to. They have to be able to defend themselves," Trump said of Ukraine July 7.

Medvedev is deputy to Russian President Vladimir Putin on the Security Council of Russia, which advises Putin on national security and strategic matters, and is himself a former president and prime minister of the country.