President Recep Tayyip Erdoğan on Monday renewed his warning to "freeze" the NATO membership bids of both Sweden and Finland unless the military alliance complies with Ankara's conditions.

At a NATO summit in Madrid at the end of June, Erdoğan called on the two countries to "do their part" in the fight against terrorism and accused them of providing a haven for outlawed PKK terrorists and its branches.

Speaking Monday, on the eve of a three-way summit with Russia and Iran, Erdoğan told reporters; "I want to reiterate once again that we will freeze the process if these countries do not take the necessary steps to fulfill our conditions".

"We particularly note that Sweden does not have a good image on this issue," the Turkish leader added.

NATO's expansion policies should go in line with the sensitivities of longtime member Turkey, said the president weeks after signing a protocol with membership hopefuls Sweden and Finland.

Referring to conditions in a memorandum the two Nordic countries signed with Turkey last month, Erdoğan warned after the Cabinet meeting in the capital Ankara: "I repeat it again that we will freeze their NATO accession process if the conditions are not met."

He added: "We see that especially Sweden does not give a good impression in this regard. Turkey's stance about this issue is very clear, the rest is their business."

Earlier this month NATO kicked off the accession procedures for Sweden and Finland after a deal was struck with Turkey, which had blocked the Nordic nations from joining. Representatives from NATO's 30 member states signed accession protocols for Sweden and Finland after formally inviting them to join the military alliance.

Spurred by Russia's war on Ukraine, the two countries applied to join NATO in May, shedding their traditional neutrality.

But Turkey voiced objections to their membership bids, criticizing the countries for tolerating and even supporting terrorist groups such as the PKK, its Syrian branch YPG and the Gülenist Terror Group (FETÖ), the group behind a defeated coup in Turkey in 2016.

Ankara and the two Scandinavian countries signed the memorandum after four-way talks, including NATO, ahead of the NATO summit in Madrid.

The agreement allows the countries to become NATO members but requires them to take steps on Turkey's terrorism concerns and lift an arms embargo on Ankara.

Following the trilateral deal, NATO formally invited Sweden and Finland to join the 30-member alliance.

In Washington, State Department spokesperson Ned Price did not respond directly when asked about Erdoğan's remarks but referred to Turkey's green light during the NATO summit to the Nordic nations' NATO membership.

"Turkey, Finland, Sweden -- they signed a trilateral memorandum in Madrid to set this process in motion," Price told reporters.

"The United States will continue to work with those three countries to see to it that this accession process and ratification -- here and around the world -- is as swift and efficient as it can possibly be," he said.