Currently exist "no preparations" for US President Donald Trump to confer with Russian President Vladimir Putin "in the near term", a administration representative has announced.
Last Thursday the US president said he and the Kremlin leader would conduct negotiations in Hungary's capital within two weeks to address the ongoing hostilities.
A preparatory meeting between America's top diplomat Secretary Rubio and his opposite number Sergei Lavrov was planned for this week - but the administration said the two had had a "productive" call and that a meeting was no longer "necessary".
The administration withheld any more details on why the talks had been postponed.
The US president had raised the possibility of a Hungarian meeting over the phone with the Russian leader, a day before meeting Ukraine's Volodymyr Zelensky in the White House.
Various sources claimed his talks with Zelensky had been a "contentious discussion", with insiders claiming Trump had pushed him to relinquish significant territories of Ukraine's east as part of a settlement with Russia.
However, on this week Trump endorsed a truce plan supported by Kyiv and European leaders to halt the war on the existing battle lines.
"Leave it as is where it stands," he said.
Moscow has frequently resisted against halting the present battle positions.
Moscow was exclusively seeking "permanent resolution", Russia's foreign minister stated on Tuesday, suggesting that freezing the front line would only amount to a brief pause.
The "root causes" of the hostilities required resolution, Lavrov emphasized, using Russian diplomatic language for a series of comprehensive conditions that involve the acceptance of total Russian authority over the Donbas as well as the demilitarisation of Ukraine – a unacceptable proposition for Ukraine and its EU supporters.
Zelensky stated conversations concerning the current lines were the "beginning of diplomacy" but that Russia was "employing all tactics" to avoid diplomacy.
He further commented the sole subject that could make Moscow "become engaged" was that of the delivery of extended-range arms to the Ukrainian military.
Putin's spontaneous discussion with Trump recently preceded rumors that the US was planning to provide distance-capable weapons to Ukraine that could potentially strike deep into Russia.
Zelensky said it was the missile discussion that had compelled Moscow to participate in talks. The discussion regarding the missiles had emerged as a "strong investment" in negotiations", he remarked.
Elara Vance is a tech journalist with over a decade of experience covering emerging technologies and consumer electronics.