Joe Biden and Polish President Bronislaw Komorowski, right, talk under Solidarity trade union flag in the presidential palace after their meeting in Warsaw, March 18, 2014. Janek Skarzynski/AFP/Getty Images

Vice President Joe Biden's trip to Poland and Lithuania had a dual mission: show support of NATO allies in Russia's backyard while also considering ways to wean these countries off their dependence on Russia, especially its oil.

And while all the leaders he met expressed a desire to work together under NATO's principle of collective self-defense, there were clear rifts, even between neighbors, over how hard to hit Russia with economic sanctions in response to its takeover of the Ukrainian region of Crimea.

Estonia's president Toomas Ilves was vehement Tuesday in his desire for the European Union to impose severe sanctions on Russia, regardless of the impact on energy supply.

"The response should not be about the price of gas," he said during a joint press statement with Biden in Warsaw, Poland.

A senior administration official told reporters during the trip that Biden had received assurances that Ilves and his Polish counterparts would call for tough sanctions on Russia during Thursday's gathering of European Union leaders in Brussels, Belgium.

But going into that meeting, not everyone in the Baltic region expressed the same enthusiasm for sanctions as their colleagues. Just after visiting with Biden Wednesday, Lithuania's Dalia Grybauskaite warned that economic sanctions on Russia would backfire on the West.

"I know how Russians think and believe me they don't care about economic sanctions. And if economic sanctions were introduced today, horizontally, this will touch every Russian citizen and will be used by Putin to say 'Look, I am not guilty it's the West, Americans and Europe who are doing bad things to you,'" she said, per the Wall Street Journal.

The president of Latvia, Andris Berzins, emphasized his desire for long-term energy independence from Russia, a goal the United States shares, over sanctions that could not only cut off his country's oil supply but throw its economy into a tailspin.

"I would like to underline the need to accelerate the construction of gas [pipeline] linking Poland to Lithuania and further on to Latvia," he said during a joint press statement with Biden and Grybauskaite in Lithuania.

Despite the divisions among the countries he visited over sanctions, Biden continuously underscored their unity on collaborating within NATO.

"Our intent is that NATO emerge from this crisis stronger and more unified than ever," he said Tuesday in Poland.

And even the optics of the visit reinforced the notion that the countries were standing together against Russia. During his visit with Polish president Bronislaw Komorowski, Biden posed with him under a flag from the country's famous anti-Soviet movement whose name contains a single English word: "Solidarity."