Turkey"s Foreign Ministry summoned Sweden"s ambassador in Ankara to a meeting to protest contacts between two Swedish ministers and members of the Syrian Democratic Forces (SDF), which Ankara considers a terrorist group, Turkish diplomatic sources said on Tuesday. Turkey considers the SDF to be an extension of the outlawed Kurdistan Workers Party (PKK) militia, which has waged a decades-old insurgency against the Turkish state. Ankara says the Syrian Kurdish YPG, which forms the military backbone of the SDF, is an offshoot of the PKK. The Turkish sources said the ambassador was summoned to the ministry over a recent videoconference between Swedish Defence Minister Peter Hultqvist and senior SDF officials, and added the call came shortly after contact between Swedish Foreign Minister Ann Linde and "terrorist elements". The ambassador was told that Turkey "strongly condemned" the contacts and that "Sweden"s dangerous politics were not just supporting those targeting Syria"s territorial integrity and Turkey"s security, but also amounted to clearly a violation of international law, and therefore continue to seriously harm our bilateral ties," the sources added. Sweden"s Foreign Ministry confirmed the summons and said the government does not meet with organisations that are on the European Union"s list of terrorist organisations. Turkey has backed rebels looking to oust Syrian President Bashar al-Assad and has carried out four cross-border operations into Syria against Russian-backed Syrian government forces, and Islamic State and the YPG, a key component of the U.S.-backed SDF that helped the United States defeat Islamic State. In a 2019 cross-border operation with the support of rebels, Turkey seized 120 km (75 miles) of border territory in northeast Syria from the YPG. The offensive was widely condemned by its Western allies, but Ankara has repeatedly urged Washington and other allies to stop supporting the YPG.