McCain told ERR News's Kaisa Kaer that it must be signaled to Russian President Vladimir Putin that the price of invading Ukrainian territory is very high. He said more drastic sanctions could be imposed, as well as holding military exercises in the Baltics and restoring the canceled plan for a US missile defense complex in Poland and the Czech Republic.

In terms of possible scenarios if the US were to send weapons to Ukraine, McCain said that it would make Russia think twice about its aggressive policies.

"I believe that if the united states provided the Ukrainian government with defensive weapons then that could help convince Vladimir Putin that further aggression into ukraine will exact a heavier price," the senator said, adding that if Putin's losses are shown to be higher, he may reconsider "his calculation".

"When Russia invaded Afghanistan many years ago, we sent lots of weapons in, and the Russians were driven out of Afghanistan and it began the collapse of Soviet Union," McCain said.

Hoeven said he believes sanctions will work if they are toughened up.

McCain said he has little belief in the EU to act quickly and decisively as the member states are currently only 'holding meetings.'

Speaking about the possible energy conflict, Hoeven said the US should begin to export gas to Europe, as the recent changes in the nation's energy industry means they have enough to export. He said infrastructure would be needed and could take years to build.