KUALA LUMPUR - Malaysia's ruling party Umno said on Sunday that former prime minister Tun Dr Mahathir Mohamad has "crossed the line" by attending the Bersih 4 rally, Bernama reported.

Dr Mahathir's attendance in the rally ran counter to a statement he made in 1998 that street demonstrations should not be supported, Umno vice-president Hishammuddin Hussein said on Sunday.

"His action has gone against the values he had promulgated when he was prime minister," Mr Hishammuddin was quoted by Bernama as saying.

"During his administration, he had clearly stated that street demonstrations were not the approach to voice dissatisfaction," Mr Hishammuddin, who is also Defence Minister, added.

Mr Hishammuddin said Dr Mahathir's freedom of expression had not been curtailed after his retirement, but his presence at an opposition rally was unacceptable.

Mr Hishammuddin's comments came after Dr Mahathir made his second appearance at the rally on Sunday, following his surprise visit one day ago.

He was accompanied by his wife Tun Dr Siti Hasmah Mohd Ali, former Umno minister Datuk Zaid Ibrahim and four bodyguards at about 4.10pm Sunday, The Star said.

He was wearing a checkered blue shirt with a hat and headed towards Central Market, where he gave an impromptu press conference.

"I am here to support the people. This is not about the Chinese or Indians or Malays. This is not about Umno, BN, PAS, DAP or whatever. This is about the feelings of the people." he said.