WARSAW: Joe Biden is not seeking 鈥渞egime change鈥� in Russia, the White House said Saturday, after the US president declared in a major speech that Vladimir Putin 鈥渃annot stay in power.鈥� 

鈥淭he president's point was that Putin cannot be allowed to exercise power over his neighbours or the region,鈥� a White House official said minutes after the speech concluded.

鈥淗e was not discussing Putin's power in Russia, or regime change,鈥� the source added.  

The Kremlin dismissed the remark, saying it was up to Russians to choose their own president.

Asked about Biden's comment, Kremlin spokesman Dmitry Peskov told Reuters: 鈥淭hat's not for Biden to decide. The president of Russia is elected by Russians.鈥�  

Still, the comments came on a day of escalating rhetoric as Biden also described branded Putin a 鈥渂utcher鈥� during a meeting with refugees who have fled the war in Ukraine to the Polish capital.

On Saturday, Biden said the West was united against Russia鈥檚 invasion but also added that NATO was a defensive security alliance which never sought Russia鈥檚 demise.

Biden鈥檚 speech was delivered at Warsaw鈥檚 Royal Castle before hundreds of Polish elected officials, students and US embassy staff, many holding US, Polish and Ukrainian flags.

鈥淭he West is now stronger, more united than it has ever been,鈥� Biden said.

Calling the fight against Vladimir Putin a 鈥渘ew battle for freedom,鈥� Biden said Putin鈥檚 desire for 鈥渁bsolute power鈥� was a strategic failure for Russia and a direct challenge to a European peace that has largely prevailed since World War Two.

Biden also said the world must prepare for a 鈥渓ong fight ahead".

鈥淲e stand with you,鈥� he told Ukrainians in the sweeping speech, which he began with the words of late Polish pope John Paul II: 鈥淏e not afraid.鈥�

He said Russia had suffered a 鈥渟trategic failure鈥� in Ukraine and told ordinary Russians they were 鈥渘ot our enemy,鈥� urging them to blame Putin for the heavy sanctions imposed by the West.

He also warned Russia not to move on an 鈥渋nch" of NATO territory, reiterating the 鈥渟acred obligation鈥� of collective defence for alliance members.

鈥淲e will have a different future, a brighter future rooted in democracy and principle, hope and light,鈥� he added.

* With AFP and Reuters