Pawel Soloch, head of the National Security Bureau (BBN), said he had strong hopes of success in convincing Ankara to let the two Nordic countries join the Alliance.

The two countries look set to ditch their traditional neutrality and apply to join the alliance in the wake of Russia’s invasion of Ukraine but their plans have run into objections from Turkey.

"Poland will be speaking with Turkey about enlarging Nato. We think we will be able to get our Turkish allies to consent to Finland and Sweden joining Nato," Soloch said.

On Friday, Recep Tayyip Erdogan, the Turkish president, said Turkey could veto both countries' Nato membership on the grounds that they provide shelter to terrorist organisations.

Soloch said that if need be, President Andrzej Duda was ready to discuss the matter directly with Erdogan.

He added that Turkey's objections were connected to "the Kurdish issue" and had been brought up on several earlier occasions in connection with Nato planning.

"The Kurdish issue is in the background here, of course. This comes up regularly when Nato is to make a decision... We believe we will manage to convince our Turkish allies," Soloch said.