Syria's President Bashar al-Assad scoffed and questioned the US actions in Syria, terming as "invaders" the American troops deployed to the country because he hadn't given permission for them to enter the country.

There's been no "concrete action" from the Trump administration towards Islamic State (IS) terror group, Assad said in an interview with Chinese media outlet Phoenix TV. It was published on Syria's state-news agency SANA on Saturday.

"Any foreign troops coming to Syria without our invitation or consultation or permission, they are invaders, whether they are American, Turkish, or any other," Assad said.

"And we don't think this is going to help. What are they going to do? To fight ISIS? The Americans lost nearly every war. They lost in Iraq, they had to withdraw at the end. Even in Somalia, let alone Vietnam in the past and Afghanistan. They didn't succeed anywhere… they only create a mess."

"… they are very good in creating problems and destroying, but they are very bad in finding solutions," said the Syrian President.

US Marines have arrived in northern Syria with artillery to support US-backed local forces fighting there, US officials said. They are preparing to move in to assault the city of Raqqa, IS's self-declared capital, according to reports.

The Pentagon and the Marine Corps have declined to confirm the deployment, citing security concerns. The US has also deployed approximately 100 Army Rangers in and around Manbij, Syria.

In the interview, Assad was asked whether there can be room for cooperation between the US and Syria.

"In theory, yes, but practically, not yet, because there's no link between Syria and the US on the formal level. Even their raids against IS happened without the cooperation or the consultation with the Syrian Army or the Syrian government, which is illegal," he said.

Assad said the Trump administration's rhetoric during and after the presidential campaign focused on defeating IS and he called that "a promising approach to what's happening in Syria and in Iraq, because we live in the same area and we face the same enemy".

But Assad also said, "we haven't seen anything concrete yet regarding this rhetoric, because we've been seeing now certain is a local kind of raids."

Assad said the approach towards terrorism needs to be "comprehensive" and not "local", reported SANA.

"It cannot be from the air, it should be in cooperation with the troops on the ground, that's why the Russians succeeded, since they supported the Syrian Army in pushing IS to shrink, not to expand as it used to be before that."