Ukraine has asked the Biden administration to provide more intelligence on the position of Russian forces and military targets inside Russia as Ukrainian troops struggle to hold ground in the war, according to U.S. and Ukrainian officials.

A group of Ukrainian parliament members also met with members of Congress in Washington to press for the United States to allow Ukraine to use U.S. weapons in Russia.

Ukraine’s requests have become more urgent in recent weeks as Russia has taken advantage of delays in shipments of U.S. weapons and intensified military operations in the Kharkiv region of northeastern Ukraine.