President Biden and Russian President Vladimir Putin, shown in June, met via video link on Tuesday. Patrick Semansky/Associated Press

KYIV — Ukrainian officials kept expectations low Tuesday that President Biden’s call with Russian President Vladimir Putin would quickly lower tensions stoked by Moscow’s troop buildup along the Ukraine border, but appeared pleased that Biden signaled U.S. resolve to stand by Ukraine.

The Biden-Putin call followed U.S. fears that Russia could be planning to send its military into eastern Ukraine, where separatists supported by Moscow have battled Kyiv’s Western-allied forces since 2014. That same year, Russia annexed Crimea from Ukraine.

Russia has dismissed the claims of an imminent military move, but has pressed for concessions that include guarantees the Ukraine would not join NATO.

“Everything is possible in life, but I would not expect any breakthroughs,” Ukraine’s foreign minister, Dmytro Kuleba, told a Kyiv talk show late Monday.

He expressed hope, however, that “Putin will hear clear signals from President Biden of what Ukraine’s partners will do if Putin launches a military operation against our country.”

A White House readout of the call said that Biden “voiced deep concern” about the Russian military escalation near Ukraine and pledged that the United States and allies “would respond with strong economic and other measures in the event of military escalation.” Biden also called for a return to diplomacy.

The national security adviser, Jake Sullivan, said Biden will talk to Ukrainian President Volodymyr Zelensky on Thursday, the Reuters news agency reported.

A Kremlin summary said Putin blamed NATO for the current tensions before the military alliance’s “dangerous” support of Ukraine, including “building up military potential on our borders.”

Putin, the Kremlin said, emphasized its demand for “reliable, legally fixed guarantees excluding the expansion of NATO in the eastern direction and the deployment of offensive strike weapons systems in the states adjacent to Russia.”

In recent days, Secretary of State Antony Blinken and Zelensky spoke by telephone to “coordinate their positions on key issues,” a statement from Zelensky’s office said Tuesday.

“In particular,” the statement added, the two men discussed “the importance of enhancing security cooperation that would assist in deterring Russia’s aggressive behavior toward Ukraine.” No further details were provided.

Although previous Ukrainian administrations have voiced a desire to join NATO, Zelensky raised the pressure this year for the alliance to issue Ukraine a “membership action plan” – effectively a road map spelling out the steps needed for Kyiv’s admission.

In November, NATO chief Jens Stoltenberg said in an interview with Axios that the alliance lacked a “consensus” about Ukraine’s membership, citing in part the country’s ongoing battle with corruption.

Ukrainian officials have also insisted that they needed to be part of any discussions that directly affected their country, such as the issue of possible NATO membership.

In an article published Sunday by the Toronto-based Globe and Mail newspaper, Ukrainian Defense Minister Oleksiy Reznikov called for military assistance from the United States, Britain and Canada outside NATO framework to help deter Russia.

Zelensky’s administration also seeks to block the implementation of Nord Stream 2, an $11 billion pipeline project linking Russia and Germany that will reduce Europe’s dependence on Russian gas via Ukraine.

Although the project was completed this summer, it still awaits final regulatory approval.

Ukraine at the moment is a major transit country for Russian gas. Once Nord Stream 2 goes online, however, Ukrainian officials say that they will lose more than $1 billion in transit fees.

In November, Germany’s energy regulator announced that two Ukrainian gas companies would be part of the Nord Stream 2 certification process, raising hopes in Ukraine that the project, which seemed at one point to be inevitable, could be held up.