Poland and the Czech Republic have refused to attend a defence ministers' meeting in Hungary over Budapest's stance on Russia's invasion of Ukraine.
Polish and Czech ministers had said they would not travel to Hungary for the planned meeting on Wednesday.
Hungary confirmed that it had postponed the planned summit of the so-called Visegrád Group (V4), featuring the Czech Republic, Hungary, Poland, and Slovakia.
"A meeting of the so-called V4 defence ministers will be held at a later date," the Hungarian defence ministry told AFP on Tuesday.
Polish defence minister Mariusz Błaszczak had earlier announced that he would "not go" to Budapest.
His decision was welcomed by the leader of the Polish opposition New Left party's parliamentary group, Krzysztof Gawkowski, who said that "the Hungarians must be punished for their pro-Russian stance."
Meanwhile, Czech defence minister Jana Cernochova said it was "not fair" to attend amid Hungary's election campaign.
"I have always supported the V4 and I am really sorry that Hungarian politicians now find cheap Russian oil more important than Ukrainian blood," she added on Twitter.
The office of Austrian Defence Minister Klaudia Tanner -- who was invited -- also confirmed he would not attend.
Differences within the Visegrad group have emerged following Russia's war in Ukraine, with Hungary stating its intentions to remain neutral.
Hungary's nationalist prime minister Viktor Orbán has condemned the invasion but has repeatedly stated that the country will not support Ukraine with military equipment.
He has also refused to support an embargo on Russian oil and gas imports.
Ukrainian President Volodymyr Zelenskyy openly criticised his neighbouring EU country in an impassioned speech to European Union leaders last week.
"You have to decide for yourself who you are with," Zelenskyy said, directly addressing Orbán.
But foreign minister Péter Szijjártó responded to Zelenskyy that "for us, the security of Hungary and the Hungarian people is paramount."
The Hungarian prime minister is seeking a fourth term in office in Sunday's parliamentary elections.