The Pentagon has halted some shipments of air defense missiles and other precision munitions to Ukraine over concerns that U.S. stockpiles are too low, two people familiar with the decision said on Tuesday.

The slowing of some weapons shipments promised to Kyiv by former President Joe Biden’s administration came in recent days, they said, adding that air defense interceptors to help knock down Russian drones and projectiles were among the items delayed.

In recent weeks Russia has intensified air attacks on Ukraine’s cities, on several nights launching hundreds of drones and missiles at a time, leading to widespread damage and an increase in civilian casualties.

Since U.S. President Donald Trump took office in January, he has softened Washington’s position toward Russia, seeking a diplomatic solution to the war in Ukraine and raising doubts about future U.S. military support for Kyiv’s war effort.

Fedir Venislavskyi, a member of the Ukrainian parliament’s national security and defense committee, called the decision to halt the shipments “very unpleasant for us”.

“It’s painful, and against the background of the terrorist attacks which Russia commits against Ukraine, it’s a very unpleasant situation,” Venislavskyi told reporters.

However, last week Trump said he was considering selling more Patriot air defense missiles to Ukraine following a meeting with President Volodymyr Zelenskiy.

Russia, which already controls about a fifth of Ukraine, has been preparing a summer ground offensive, advancing gradually in the eastern region of Donetsk and northeastern region of Sumy.

Ukraine is already experiencing a shortage of 155 mm ammunition used for artillery on the front lines, said one Ukrainian defense source, calling the shortages and news of delays in U.S. supplies “all quite sad”.

In an email, the Pentagon said it was providing Trump with options to continue military aid to Ukraine in line with the goal of ending Russia’s war there.

“At the same time, the department is rigorously examining and adapting its approach to achieving this objective while also preserving U.S. forces’ readiness for administration defense priorities,” said Elbridge Colby, the undersecretary for policy.

All weapons aid was briefly paused in February with a second, longer pause in March. The Trump administration resumed sending the last of the aid approved under Biden.

No new policy has been announced.