WASHINGTON >> In the early phase of the war in Ukraine, shortages of soldiers and problems with equipment forced Russia to narrow its mission, abandon its assault on Kyiv and focus its offensive on the east.

Now, as the fighting enters its sixth month, critical manpower and equipment problems could again slow Russian operations and give Ukraine’s counteroffensive a better chance to succeed, U.S. and European officials said.

The signs of Russia’s challenges abound: artillery shells missing their targets, intercepts of Russian soldiers complaining they have been given old tanks and a sharply rising death and injury toll in its military ranks.

But unlike earlier in the war, it could become harder for Russia to reset its strategy and recover, at least in the short term.

U.S. and European officials say few powers have conquered a country and destroyed an opposing army with a mostly volunteer force, as President Vladimir Putin of Russia is attempting to do. But Putin has shown no indications that he wants any sort of full-scale draft, which would amount to an admission to his country that the fight in Ukraine will be a long war, not a short operation.

Russia has announced, and the West has predicted, various pauses in the war. After the fall of the city of Lysychansk last month, for example, Russian commanders said their forces would pause and reset, but artillery attacks continued.

This time, NATO and other officials say the reality on the ground should force the Russian military to slow its operations to reinforce depleted units, better protect its supply lines and move in new equipment. These officials concede it is possible that Putin could override the advice of his officers and order the drive in the east to continue through the summer. Moscow is making enough money to fund its military.

The expected Russian pause comes after the bloodiest phase of the war for both sides. Ukraine and Russia have lost thousands of soldiers, including some of their best and most experienced front-line troops, during the last weeks of a grinding artillery battle that destroyed cities and towns in the path of Moscow’s army.

The Russian shortfalls have created an opportunity for the Ukrainian army, driving their decision to launch a counteroffensive, said senior U.S. military officials and U.S. lawmakers who have visited Ukraine recently. More Ukrainian offenses, most likely in the south, are likely in the coming weeks, these officials said.

“The Russians are exhausted, and you don’t want to give them time to regroup and rest,” said Rep. Elissa Slotkin, D-Mich., a member of the House Armed Services Committee who visited Ukraine last month with a small group of lawmakers.