Putin preparing for prolonged conflict in Ukraine, says US spy chief

'We assess Putin is preparing for a prolonged conflict in Ukraine during which he still intends to achieve goals beyond the Donbas,' US Director of National Intelligence Avril Haines told lawmakers

The United States believes that Russian President Vladimir Putin is preparing for a long conflict in Ukraine and a Russian victory in the Donbas in the east of the country might not end the war, U.S. Director of National Intelligence Avril Haines said on Tuesday.

Russia's assault on Kyiv was beaten back in March by strong Ukrainian resistance.

Russia, which calls the invasion "a special military operation," poured more troops into Ukraine for a huge offensive last month in the eastern part of the country but its gains have been slow.

"We assess President Putin is preparing for a prolonged conflict in Ukraine during which he still intends to achieve goals beyond the Donbas," Haines told lawmakers.

She added that Putin was counting on the Western resolve to weaken over time and as the conflict continued, there was concern about how it would develop in the coming months.

"Combined with the reality that Putin faces a mismatch between his ambitions and Russia's current conventional military capabilities, likely means the next few months could see us moving along a more unpredictable and potentially escalatory trajectory," Haines added.

During the same hearing, the head of the Defense Intelligence Agency (DIA) said the war was at a stalemate.

"The Russians aren't winning and the Ukrainians aren't winning and we're at a bit of a stalemate here," said Lieutenant General Scott Berrier, the head of the DIA.

President Vladimir Putin exhorted Russians to battle in a defiant Victory Day speech on Monday but was silent about plans for any escalation in Ukraine despite Western warnings he might use his Red Square address to order a national mobilisation.

Russia's war has killed thousands of civilians, sent millions of Ukrainians fleeing and reduced cities to rubble.

Moscow has little to show for it beyond a strip of territory in the south and marginal gains in the east.