KUALA LUMPUR (THE STAR/ASIA NEWS NETWORK) - The scheduled Nothing2Hide dialogue between Prime Minister Datuk Seri Najib Tun Razak and NGOs on the subject of 1Malaysia Development Board (1MDB) has been cancelled following a Twitter message by the Inspector General of Police saying it would not allow be allowed.

In his tweet at about 8.50am, Tan Sri Khalid Abu Bakar said the event was cancelled on orders from police due to public safety.

Tun Dr Mahathir Mohamad, who had been waiting in a VIP room for the event to start, emerged from his room to thunderous applause and addressed the crowd.

"I come here today to speak on something that is missing, that belongs to all of us," the former premier began. "Are we independent or are we still colonised"

"He (Mr Najib) gives in too much to Singapore, America," he added.

Dr Mahathir's speech was cut short when police cut off two large video screens showing his speech. A few officers also went on stage to stop him from continuing. His supporters in the crowd yelled "no" and "long live, Tun (Dr Mahathir)".

After his speech was disrupted, the 89-year-old sat down on stage and spoke to the press without a microphone.

Organisers said they are negotiating with the police to start the forum.

Mr Najib and 1MDB have faced criticisms for debts which were said to have been incurred by the investment body.

Dr Mahathir had questioned 1MDB's proposed restructuring plan, saying the move would only give control of the company to Abu Dhabi-based International Petroleum Investment Company (IPIC).

"There is too much evidence of cover-ups by politicians and civil servants," he had posted on his blog chedet.cc.

"I hope the restructuring will help but unless the lost money is returned, paying off the debt will absolve no one," he added.

Dr Mahathir said 1MDB would gain nothing from the transaction because the IPIC money would be used to slash its RM42 billion (S$15.25 billion) debt to a smaller amount.

With additional reporting from Amy Chew