Turkey has accused Sweden of providing a safe haven for dozens of suspects it believes are linked to a failed 2016 coup attempt and a decades-long Kurdish fight for an independent state, and has therefore held back on ratifying its NATO application.

Sweden's justice ministry said it had agreed to the extradition of Omer Altun, a 29-year-old Turkish citizen sentenced last year by a Turkish court to 15 years in prison for "what in Sweden would be the equivalent of fraud."

The ministry said the extradition was only agreed on the condition that Altun would be granted a retrial upon his return to Turkey.

The decision, a copy of which was obtained by AFP and was dated March 30, came after Sweden's Supreme Court gave the green light for the extradition.

"The government shares the Supreme Court's assessment that there is nothing blocking the extradition of Omer Altun to Turkey," it said.

- Independent judiciary -

Stockholm has repeatedly stressed that its judiciary is independent and has the final say in extraditions.

The government did however reject an extradition request concerning 51-year-old Mehmet Zakir Karayel, a Swedish citizen whom Ankara suspects of being a member of an "armed terrorist organisation", according to documents from the Swedish justice ministry.

Under Swedish law, "a Swedish citizen cannot be extradited", it wrote.

The Scandinavian country has extradited at least two Turkish citizens in the past year but rejected requests for several others, including one for the former editor-in-chief of the Zaman daily, whom Turkey accuses of being involved in a 2016 attempt to topple President Recep Tayyip Erdogan.

In a historic turnaround, Sweden and Finland abandoned their longstanding policies of military non-alliance and applied to join NATO after Russia invaded Ukraine.

After months of delay, Ankara ratified Finland's membership last month, enabling it to become of a full member of the defence alliance this week.