Vice President Mike Pence said he hopes his trip in Eastern Europe shows the Baltic States the United States stands with them.

"President Trump sent me to Europe with a very simple message. And that is that America first doesn't mean America alone," he said in an interview with Fox News during a stop in Tallinn, Estonia

"Our message to the Baltic states, my message when we visit Georgia and Montenegro, will be the same: To our allies here in Eastern Europe, we are with you, we stand with you on behalf of freedoms. It's a great honor to be with you," Pence added.

Pence and second lady Karen Pence arrived in in Eastern Europe on Sunday afternoon, part of a three-country visit to Estonia, Georgia, and Montenegro.

The vice president's visit comes amid tensions between NATO and Russia.

In a statement, Estonian Prime Minister Juri Ratas said cooperation between the U.S. and the Baltic States is "vital."

"The contribution of the US to the security of the Baltic States and also the whole of Europe is vital, and I certainly wish to thank the vice president for that. Besides that, we plan to speak about the Estonian digital solutions that are of interest to the US, and developing cooperation in cyber defense at our meeting. Another important topic that will be on the table, is the cooperation between the [European Union] and the US," Ratas said in a statement.

Pence tweeted early Sunday morning he had arrived and was ready to talk about "security and prosperity" with the Baltic States' leaders.

When asked if the Trump administration is "committed" to defending the Baltic States, Pence responded affirmatively.

"Well, the president has made it very clear that Russia's destabilizing activities, its support for rogue regimes, its activities in Ukraine, are unacceptable. The president made very clear that very soon he will sign the sanctions from the Congress of the United States to reinforce that. But at the same time, as we make our intentions clear, we expect Russian behavior to change," he said.

Trump is expected to soon sign legislation imposing new sanctions on Russia, which has caused President Vladimir Putin to retaliate and pull U.S. diplomats from Moscow.