According to Erdogan's office, the president made these comments during a phone call with Dutch Prime Minister Mark Rutte, Middle East Eye reported.

"President Erdogan said Sweden has taken steps in the right direction by making changes in anti-terrorism legislation," the statement said.

"But supporters of the PKK... terrorist organisation continue to freely organise demonstrations praising terrorism, which nullifies the steps taken," it quoted him as saying.

The statement comes amid doubts over whether Ankara will withdraw its opposition to Sweden's entry into Nato before the upcoming alliance's summit, the 2023 Vilnius Summit, set to take place in Lithuania on 11 July.

Last month, Erdogan downplayed Sweden's prospects of joining Nato at the forthcoming summit in Vilnius, saying that Stockholm had failed to fulfil its commitments, particularly with recent permissions granted to supporters of the PKK to stage protests.

Erdogan told journalists accompanying him to Azerbaijan in June that "terrorists" were demonstrating in the streets of Stockholm while Nato Secretary-General Jens Stoltenberg had been trying to convince him to accept Sweden's bid for membership of the military alliance.

"While Stoltenberg was expressing these views to us, unfortunately, at that time, terrorists were demonstrating in the streets again in Sweden," he said. "Now, we cannot approach this work positively within this table."

Last month, supporters of the PKK rallied, waving their flags and staging protests against Turkey.

Turkey holds veto power over any potential entrants into the alliance and has pledged to exercise this power until its concerns over the purported PKK presence in Sweden are resolved.