Home Minister Ahmad Zahid Hamidi has disclaimed any responsibility in the cancellation of Prime Minister Najib Abdul Razak's dialogue with NGOs this morning.

Ahmad Zahid said he was only involved in policy matters and not operational matters.

"The police received information that there was (untoward) incidents... eventough the event was meant to expose something that shouldn't be hidden," he told reporters in Putrajaya, according to Bernama.

Ahmad Zahid said the prime minister was very sad that the event was cancelled, because he was very committed towards it.

On the police decision to stop Mahathir's speech mid-way during his speech, Ahmad Zahid said the police will explain themselves later today.

The event, dubbed "Nothing to hide", was organised by SukaGuam, a NGO which provides legal advice. SukaGuam is led by Johor Umno Youth deputy chief Khairul Anwar Rahmat.

On June 2, Khairul said the event was a platform for Najib to address NGOs from across the country. He added he will personally invite Mahathir as well.

Mahathir turned up for the event at 8.50am and was brought to a VIP holding room. He emerged after it was confirmed that Najib would not be attending due to security reasons.

For reasons unknown, an announcement was made that Mahathir would address the crowd, numbering around 2,000 people, instead.

About 10 minutes through his speech, Mahathir's microphone was turned off and police led him off the stage.