Riyadh, Feb 4 (IANS): Saudi Arabia's King Abdullah bin Abdulaziz Al Saud ordered Monday the imprisonment of Saudi citizens who fight outside the country with prison terms ranging between 3-20 years, the Saudi Press Agency said.

Members of local, regional and international extremist and terrorist groups will also be imprisoned under the ordinance, Xinhua reported. Military personnel convicted will have harsher sentences, ranging from 5-30 years.

The king formed a committee of members from various government organisations to draft and update a list of illegal groups.

The decision comes as many officials fear a growing number of youths having gone to fight in the two-year-old conflict raging in Syria.

Saudi Arabia has long maintained the Syrian government should not stay in power considering the growing crisis, saying there is "no role" for Syrian President Bashar al-Assad in peace talks about Syria's future, while the Syrian administration has long accused Saudi Arabia of backing jihadist groups fighting to topple the president.