"Last week, the US Defense Department informed the countries that, starting from its next financial period, funding will be reduced to zero," the defence policy director in Lithuania's defence ministry, Vaidotas Urbelis, told reporters.

The decision comes as US President Donald Trump struggles to end Moscow's three-and-a-half-year invasion of Ukraine.

Urbelis confirmed reports in The Washington Post and The Financial Times citing unnamed officials saying the move was part of Trump's efforts to cut US expenditure abroad.

The FT said US officials had told European diplomats last week that Washington would no longer fund programmes to train and equip eastern European militaries along Russia's border.

The Washington Post said the funding to be cut was worth several hundreds of millions of dollars.

In Lithuania's case, the cuts would impact "the purchase of US weapons and other equipment, and training", Urbelis said.

He added that it "will not have an impact on the US troop presence in the region", which was funded through a separate US budget allocation.

A White House official said the move hewed to a January executive order Trump had signed that reevaluated US foreign aid.

"This action has been coordinated with European countries in line with the executive order and the president's longstanding emphasis on ensuring Europe takes more responsibility for its own defence," the official said on condition of anonymity.

Trump has long been sceptical of both US defence spending in Europe and aid for Ukraine, pushing some of Washington's closest allies to play a greater role on both fronts.

The Lithuanian defence ministry official said that the US funding for training and equipping its military covered between a third and 80 percent of total military aid received by the country.

Estonia's Defence Minister Hanno Pevkur told the Postimees daily that he viewed the US move as "especially symbolic, in a negative way".