Former prime minister Tun Dr Mahathir Mohamad said the trend towards stressing "state citizenship" could break up the unity of Malaysians.

He stressed that all states should promote the idea of being Malaysian, rather than the idea of being people of different states, saying that only by unity could Malaysia prosper.

"The Federal Constitution does not allow for secession. We should call ourselves Malaysians not Johoreans, Kedahans etc because it tends to break up the unity of the people.

"I do not want to see it go beyond that. We are all the same, nobody is superior to others, we are all Malaysians," he said at the 20th Perdana Discourse Series titles "The Federal-State Relations in Malaysia" at the Perdana Leadership Foundation, here today.

He said this when responding to question from the audience about "Bangsa Johor" (calling oneself a citizen of the state of Johor).