A meeting of the United Nations Cultural Organization's World Heritage Committee (UNESCO), which was due to be held in Russia in June, has been postponed indefinitely, according to a source, following weeks of heated diplomatic squabbling precipitated by Russia's military operation in Ukraine.

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The Russian envoy to UNESCO advocated delaying the summit, which was to be hosted by the Russian city of Kazan, and its indefinite postponement has now been formally confirmed, a senior UNESCO source told AFP on condition of anonymity.

According to the source, the Ambassador, as the current President of the World Heritage Committee, purportedly submitted the suggestion in a letter to fellow committee member nations, and it was formalized since no objections were received as per his claims.

The summit is notable for choosing each year which sites and monuments will be granted the organization's coveted World Heritage classification – and which may be deprived of the name if governments fail to care for them.

The gathering, which was scheduled from June 19 to 30, was one of the few international events that Russia had booked after the war in Ukraine.

However, a coalition of mostly Western nations, led by the UK, had begun a campaign pressing existing committee members not to allow Russia to host the event.

One diplomat at the agency who spoke on condition of anonymity stated that "this consensus makes it possible to approach things calmly and to avoid that world heritage, which is normally a cause for harmony, does not find itself caught up in a war."