If 1MDB president and executive director Arul Kanda had no qualms accepting the debate challenge twice amid ongoing probes, what prompted him to use this as an excuse to evade the verbal jousting match now, asked DAP lawmaker Tony Pua.

"If it was okay to debate then, surely the excuse cannot apply today?" he said in a statement.

Yesterday, Arul announced he would withdraw from the debate because of the police probe into 1MDB and ongoing legal dispute with International Petroleum Investment Co (IPIC)

"I am now fully focused on assisting the police, and resolving the IPIC dispute.

"As such, I cannot engage in a debate which may prejudice 1MDB’s legal position in relation to the investigation and the dispute," he had said.

However, Arul appeared to have no such reservations last October.

He was also open to the matter when Pua revived the debate challenge last month.

He told Pua to "bring it on" when the dare was made and even took a swipe at the DAP lawmaker, telling him to check with Dewan Rakyat speaker Pandikar Amin Mulia whether a debate was possible to avoid "being embarrassed a second time."

However, Pua said he preferred not to gloat over the latest development, and refrained from hurling insults.

On the same note, the Petaling Jaya Utara MP wondered if there was a different reason behind Arul's decision.

"What is perhaps the real reason...  Is that all the pretense that 1MDB has undergone a successful 'rationalisation exercise' has collapsed, probably irrecoverably.

"More specifically, it has now been proven that 1MDB has paid US$3.51 billion, a figure provided by 1MDB themselves to the auditor-general, to a fraudulent 'Aabar Investment PJS Limited', a company set up in the British Virgin Islands, which is completely unrelated to Abu Dhabi’s Aabar Investment PJS, the subsidiary to IPIC," he added.

Pua said the cancellation of the debate would not deter the opposition's mission to uncover the truth behind the 1MDB scandal.