A rare spat between traditional allies Moscow and Belgrade was triggered apparently by the Russian foreign ministry spokeswoman ridiculing Serbia’s president after he signed a US-sponsored agreement between his nation and Kosovo.

Maria Zakharova posted a photo showing Vucic sitting across US President Donald Trump at his Oval Office table.

She posted that along with another photo, the scene from thriller “Basic Instinct” showing Sharon Stone being questioned by police as she sits cross-legged in a chair.

Zakkharova mocked Vucic in a comment on the Facebook post, saying that he was invited to the White House to be interrogated.

This did not go down well with Serbian President Aleksandar Vucic and other officials.

“The primitivism and vulgarity she showed speaks about herself, but also about those who have given her the job,” Vucic told the pro-government Pink TV.

Marko Djuric, an official with Vucic’s ruling party, defended him on Twitter. “This president did not say a single bad word against Russia, not even in that place (the White House.) The president waited for an hour and half to be received by the Russian president and never asked for a special chair. I will not allow you to attack proud Serbia. Shame on you!” Djuric wrote.

Zakharova apologised on Twitter later Sunday, saying her post had been misinterpreted.

Trump announced Friday that former wartime foes Serbia and Kosovo had agreed to normalise economic ties as part of US-brokered talks that include Belgrade moving its Israeli embassy to Jerusalem, and mutual recognition between Israel and Kosovo.

The announcement provided Trump with a diplomatic win ahead of the November presidential election and furthers his administration’s push to improve Israel’s international standing.