Sharif Shehadeh told The Associated Press on Saturday that the troops will have no effect on the ground, but Washington wants to say that it is present in Syria.
American officials say up to 50 special operations troops will be sent to assist Kurdish and Arab forces in northern Syria.
A US-led coalition has been targeting the Islamic State in Iraq and the Levant (ISIL) group with airstrikes since September 2014, killing 12,000 extremists without weakening the group.
The decision to send US troops to Syria comes a month after Russia began launching airstrikes against militants in the country.
Russia's airstrikes were agreed upon with the Syrian government.