The talks were due to be held next month, the reports said, citing Turkish diplomatic sources.

Turkey's decision came a day after President Recep Tayyip Erdogan warned Sweden he would not support its bid to join the Western US-led defence alliance.

Bids to join NATO must be ratified by all members of the alliance, of which Turkey is a member.

Ankara has been outraged by the burning of the Koran by an anti-Islam protester outside its embassy in Stockholm over the weekend.

The protest was approved by the Swedish police, despite Turkey's fierce objections.

Erdogan's comments and Tuesday's postponement diminishes Sweden and Finland's prospects of joining the bloc before Turkey's parliamentary and presidential polls in May.

Finland hinted for the first time on Tuesday that it might consider joining NATO without Sweden because of Stockholm's diplomatic problems with Ankara.

Previous rounds of the tri-party NATO talks have been attended by foreign ministry officials and focused on a specific list of Turkish demands, which include the expulsion of dozens of mostly Kurdish suspects.

Turkey and Hungary are the only NATO members not to have ratified the Nordic neighbours' historic decision to break their tradition of military non-alignment in response to Russia's invasion of Ukraine.

Hungarian Prime Minister Viktor Orban has promised his parliament would approve the two bids next month.