Turkey’s lira weakened slightly on Wednesday as investors pondered prospects for Ankara’s planned incursion in northeast Syria, with an aide of President Tayyip Erdogan saying Turkish forces will cross the border “shortly.”

Erdogan’s communications director Fahrettin Altun made the comment overnight in a tweet and in a Washington Post column as a surprise withdrawal of US troops made way for the Turkish offensive against a Syrian Kurdish militia.

The lira traded at 5.8415 at 0542 GMT, easing from a close of 5.8350 on Tuesday. It hit its weakest level in more than a month this week.

The lira has been pulled in both directions this week by comments from US President Donald Trump. A day after warning he could obliterate Turkey’s economy if it went too far in its Syria operation, Trump tweeted on Tuesday that Ankara was a big trading partner of the United States and had been good to deal with.

The extensive area of Ankara’s planned incursion into Syria could lead to months of military activity that raises concern in the markets, dealers say.

Tensions between the United States and Turkey have been simmering in recent months over issues including Ankara’s purchase of Russian missile defence systems and disagreements over policy in Syria. Turkey’s lira weakened slightly on Wednesday as investors pondered prospects for Ankara’s planned incursion in northeast Syria, with an aide of President Tayyip Erdogan saying Turkish forces will cross the border shortly.