"There is no plan to open a formal office in Syria but our people will fight against the forces of Bashar al-Assad," a Taliban source said.
"In the first step, mostly trainers, who are expert in guerrilla warfare, are going there," the source said.
Taliban sources said the fighters shifting from Pakistan to Syria included Arab, Uzbek and Chechen extremists who had been living in the mountainous tribal regions since the invasion of Afghanistan in 2001.
The Syrian situation is inviting for Taliban and their Salafi Arab supporters and fighters, who have a natural sympathy for the anti-government forces of mostly Sunni Muslims pitched against the Shia ruler al-Assad.
It is also believed that continuous US drone attacks and repeated operations by Pakistani forces have considerably weakened the foreign fighters and reduced their ability to launch organised attacks.