“I am of the opinion that these measures will only complicate further an already complicated situation,” said Turkish Defense Minister Hulusi Akar, quoted by state-run news agency Anadolu.

“We have told our American counterparts about our unease several times,” Akar said, noting that he recently raised the issue with Joe Dunford, head of the US joint chiefs of staff.

US Defense Secretary Jim Mattis said on Wednesday that Washington wanted the observation posts along Syria’s northern border with Turkey to help minimize tensions between the Turks and Washington’s Kurdish allies in the fight against the IS group.

The aim was to ensure the Syrian Democratic Forces (SDF), which includes the Syrian Kurdish YPG militia, “are not drawn off that fight.”

“They will be very clearly marked locations day and night so that the Turks know where they’re at,” he said, noting that the decision was taken in close co-operation with Turkey.

Akar, again urging Washington to halt support for the YPG, said the observation posts would serve no use.

Turkey “will not hesitate to take the necessary measures on the other side of its borders to face up to the risks and threats which could result,” he added.

The SDF announced on Nov.11 it would resume its offensive against IS after having previously called it off due to tensions with Turkey, which had shelled its positions in northern Syria.

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