Blinken stressed that the US would "never recognize the legitimacy or outcome of these bogus referendums or Russia's alleged annexation of Ukrainian territory." The actions of Russia's allies in Ukraine violate international law and are "an affront to the principles of international peace and international security".

After the "referendums" in the occupied regions of Donetsk, Luhansk, Cherson and Zaporizhia on Friday, Russia wants to complete the annexation of the areas. Kremlin spokesman Dmitry Peskov said the agreements on the admission of the regions should be signed at a ceremony with President Vladimir Putin.

Blinken said the US would "resolutely support the unity, sovereignty, independence and territorial integrity of Ukraine within its internationally recognized borders." "The US and our allies and partners will continue to assist Ukraine in its struggle to defend its territory against Russian aggression."

Meanwhile, the US Senate in Washington approved an interim budget that also includes more than $12 billion in additional aid to Ukraine. Around $3 billion of this is earmarked for training, equipping and paying the Ukrainian army and more than $4.5 billion for financial and economic aid for the government in Kyiv.

US aid to Ukraine has risen to more than $65 billion since the beginning of the year. The interim budget now has to be approved by the House of Representatives.