Ankara, Jun 4 (IANS): Turkish President Recep Tayyip Erdogan has told NATO Secretary-General Jens Stoltenberg that Turkey's security concerns on Sweden and Finland's intention to join the alliance were based on "just and legitimate" grounds, according to a statement from the Turkish presidency.

"Both countries should clearly display that they have given up supporting terrorism, that they have lifted sanctions against Turkey, and that they are ready to show alliance solidarity," Erdogan told the NATO chief in a phone call, Xinhua news agency reported.

Stoltenberg stressed the "necessity to meet the expectations of Turkey, an important ally."

Sweden and Finland formally applied to join NATO following the Russia-Ukraine conflict that erupted in late February.

NATO allies, except for Turkey, have welcomed the Nordics' appeal. Ankara, however, citing the Swedish and Finnish ties with the Kurdistan Workers' Party (PKK) and other anti-Turkey outlawed groups, objected to their entry into the alliance.

Turkey demanded an array of "concrete assurances" from Sweden and Finland, which included "termination of political support for terrorism," "elimination of the source of terrorism financing" and "cessation of arms support" to the PKK and its Syrian Kurdish offshoot.

The demands also include the lifting of the two countries' arms sanctions against Turkey.