Soylu, a member of President Recep Tayyip Erdogan’s AKP party, accused election monitors from Sweden’s Oy ve Otesi (Vote and Beyond) of putting pressure on voters at polling places.
"The Swedish state is funding this Oy ve Otesi association. Sending it money, but why? To interfere in the election in Turkiye. It is so obvious and clear," the minister told a campaign rally in Istanbul, as quoted by the Aydinlik newspaper.
Soylu is known for his harsh criticism of the West. He accused the United States on Wednesday of trying to influence the election, which will see Erdogan and his opposition challenger, Kemal Kilicdaroglu, face off in the second round on May 28.