WASHINGTON, Sept 13 - The U.S. will seek to provide Ukraine more weapons and expand training after the Ukrainian offensive forced Russian troops into a messy retreat over the weekend in the Kharkiv region, officials said Tuesday.

“Ukraine is now clearly making durable changes in its east and north and I believe that if the West properly equips Ukraine, they’ll be able to hold on to their gains,” said Philip Breedlove, a retired U.S. Air Force general who was NATO’s top commander from 2013 to 2016, The Associated Press reported.

U.S. lawmakers pointed to the precision weapons and rocket systems that the U.S. and Western nations have provided to Ukraine as key to the dramatic shift in momentum, including the precision-guided High-Mobility Artillery Rocket System, or HIMARS, and the High-speed Anti-Radiation Missile, or HARM, which is designed to target and destroy radar-equipped air defense systems.

“They’re there, they’re in theater, and they’re making the difference,” Sen. Chris Coons, a Delaware Democrat and member of the Senate Foreign Relations Committee. In the hands of highly motivated Ukrainian fighters who are making the most of weapons ranging from off-the-shelf drones and abandoned Russian arms to advanced weapons from the West, the HIMARS are enabling Ukrainians “to turn the tide, dramatically,” Coons said.

Meanwhile, a senior defense official said the U.S. is looking at future needs, including discussions about providing more intensive combat training for larger Ukraine units, a change from current training focused on smaller teams learning to handle specific weapons. It is also considering sending additional air defense systems, as well as lethal strike drones and more surveillance drones. The official was one of two who briefed reporters Monday on condition of anonymity to discuss planning details.

Ukraine’s launch in recent days of a much-anticipated counteroffensive — in a different part of the country from where Russian troops occupying Ukraine had massed strength to meet it — has brought on the biggest territorial changes in months in the 200-day war, launched when Putin rolled Russian forces into the neighboring country, targeting its Western-oriented government.

The U.S. officials acknowledged that the U.S. provided information to help the Ukrainian counteroffensive, but declined to say how much or if Western officials helped strategize the idea to throw Russian forces off guard by calling attention to attack plans in the south, while actually plotting a more formidable campaign in the east.

The U.S provided information “on conditions” in the country, said one of the officials, but “in the end, this was the Ukrainian choice. The Ukrainian military and the Ukrainian political leadership made the decisions on how to conduct this counteroffensive.”

Ukrainian forces claimed Monday to have retaken a wide band of territory and more than 20 Ukrainian settlements from Russia, pushing all the way back to the two countries’ northeastern border. Russian soldiers were surrendering in such numbers that Ukraine was having difficulty making room for them, Ukrainian military officials said.

Ukrainians have pounded 400 targets in all with the HIMARS since the U.S. began supplying them, using them “with devastating effect,” Army Gen. Mark Milley, chairman of the Joint Chiefs of Staff, told reporters late last week as Ukraine’s counteroffensive was getting underway.

The truck-mounted, GPS-guided systems fire faster, farther and more precisely than the Soviet-designed rocket launchers otherwise used by both Russia and Ukraine. They can hit targets up to 80 kilometers (50 miles) away. Ukrainian forces have used the 16 HIMARS and several similar systems to strike supply lines, ammunition depots and other key Russian targets.

Ukrainian leaders are pressing for more weapons — including fighter jets and the longer-range Army Tactical Missile System, or ATACMS, a surface-to-surface missile that the U.S. has so far declined to send.

The White House has asked Congress to greenlight an additional $11.7 billion in aid as part of an overall government funding measure that lawmakers must approve before the end of the month.

The U.S. — the lead contributor to Ukraine’s war effort among NATO members — has poured more than $15 billion in weapons and other military support into Ukraine since January. (ap/ez)