Turkey’s President Recep Tayyip Erdogan on Monday ratcheted up his objection to Sweden and Finland joining NATO.

Erdogan accused the countries of failing to take a clear stance against Kurdish militants and of imposing military sanctions on Turkey.

“Neither country has an open, clear stance against terrorist organizations,” Erdogan said at a joint news conference with the visiting Algerian president. “We cannot say ‘yes’ to those who impose sanctions on Turkey, on joining NATO which is a security organization.”

The Turkish leader described Sweden as an “incubation center for terrorist organizations,” claiming some members of its parliament supported the outlawed Kurdistan Workers’ Party, or PKK. The group has waged an insurgency against Turkey since 1984, costing tens of thousands of lives.

Erdogan said Swedish and Finnish officials — who are expected in Turkey next week — should not bother to come if they hope to convince Ankara into relaxing its objections to their membership.