Senate Foreign Relations Committee leaders Robert Menendez (D-N.J.) and Bob Corker (R-Tenn.) were on “Fox News Sunday” to discuss the situation in Crimea.

According to an election official, Crimea has voted to break away from Ukraine, and there has been an incursion 6 miles further into Ukraine. But how far will Russian President Vladimir Putin go?

“Well, President Putin has started a game of Russian roulette and I think that the United States and the west have to be very clear in their response because he will calculate about how far he can go,” Menendez said. He thinks the west must have robust sanctions ready to go.

The Russians have troops along the border of eastern Ukraine, but they're still in Russian territory. “I think it's a show of intimidation, but the fact is that we do have to show resolve,” Corker said.

If Russia moves toward accepting annexation, Menendez said that having sanctions ready to go will send a clear message.

Wallace asked Corker about Secretary of State John Kerry’s recent remarks, where he said “We hope President Putin will recognize that none of what we're saying is meant as a threat, it's not meant as a -- you know, in a personal way.”

“Well, look, there's no question that I think our administration has created an air of permissiveness, and [...] I think that it's those comments that caused Putin to question what our resolve is,” Corker said. Corker called the current situation a “defining moment for us and for Europe,” noting that we need to be strong now.

Watch what the two senators had to say in the video above.

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