Parti Pribumi Bersatu Malaysia (Bersatu) Youth chief Syed Saddiq Abdul Rahman was questioned by police over his open letter to the Johor sultan over the state ruler's ban against street protests in the southern state.

He gave his statement to police at 3pm today at the Bukit Aman police headquarters.

"To be honest, I never thought at any point in my life that I would be labeled a traitor to my sultan, the sultan of Johor.

"Those who know me will know how much I love the royal institution of Johor and the state of Johor.

"This will not break my spirit to continue to struggle and contribute to the state and country that I love," Syed Saddiq said in a Facebook posting.

This comes after several NGOs lodged reports against Syed Saddiq for allegedly disrespecting the sultan with his open letter.

They said the sultan was only looking out for peace and harmony when he barred street protests in Malaysia in a Nov 3 decree.

Constitutional experts, however, said the sultan's decree is not binding.

The Federal Constitution safeguards citizens' rights to assembly.