Turkey has been taking a harder stance on Sweden's bid to join the North Atlantic Treaty Organization, or NATO. The move comes after spreading protests across the Middle East triggered by the burning of a copy of the Koran in Sweden.

A leader of a far-right group set fire to the Islamic holy book in front of the Turkish Embassy in Stockholm on Saturday.

Condemnation of the act is spreading in the Middle East. In Jordan, protestors gathered in front of the Swedish Embassy, saying the Koran is the word of God.

Turkish President Recep Tayyip Erdogan referred to Sweden's bid at a news conference on Monday. He said those who allow such blasphemy in front of Turkey's Embassy can no longer expect the country's support for NATO membership.

Following Russia's invasion of Ukraine, Sweden and Finland applied to join the alliance. Turkey has been demanding that the two Nordic countries undertake anti-terrorism measures as a condition for Ankara to approve their membership. The Turkish government accuses both countries of harboring separatist Kurdish militants.

Observers say the outlook for Sweden's bid has become more uncertain as Erdogan has shown intent to hold presidential and parliamentary elections on May 14.