Anwar said he had personally authorised the installation of "one of the most sophisticated radar" systems in the world, based near the South China Sea and covering Malaysia's mainland and east and west coastlines, when he was the country's Finance Minister in 1994.
The 66-year-old was once Deputy Prime Minister in Malaysia's ruling coalition. But after falling out with the country's leaders, he was charged with sodomy, imprisoned twice and beaten. He now leads a pro-democracy coalition of parties that lost last year's election, despite winning more than 50 per cent of the popular vote, amid allegations of Government corruption.
Anwar said it was "not only unacceptable but not possible, not feasible" that the plane had not been sighted by the Marconi radar system immediately after it changed course. The radar, he said, would have instantly detected the Boeing 777 as it travelled east to west across "at least four" Malaysian provinces.
Anwar said it was baffling the country's air force had remained silent, and claimed it "should take three minutes under [standard operating procedure] for the air force planes to go. And there was no response". He added: "We don't have the sophistication of the US or Britain but we have the capacity to protect our borders."
He said the families of 153 Chinese victims on board were right to demand information from the Malaysian Government, which let a multi-national search operation to spend a week looking in what it must have known was the wrong place.
"Why didn't we alert the Chinese, the Vietnamese that the operation should cease in the South China Sea and let them spend millions on search and rescue in a place they know fairly well cannot be the site of the plane?"
As hope fades of recovering the plane's black box before its batteries start to fail, which could be as early as Monday, Anwar said it was "at the least, incompetence" on the part of the Malaysian Government that it's still not known what happened to the plane, but was also a deliberate "intention to suppress key information".
He said: "Unfortunately the manner in which this was handled after the first few days was clearly suspect. One fact remains. Clearly information critical to our understanding is deemed missing.
"I believe the Government knows more than us. They have the authority to instruct the air force, or Malaysia Airlines. They are privy to most of these missing bits of information critical to our understanding."
Anwar indicated it was possible officials on the ground were complicit in what happened on the plane. However, he later added that "the realm of possibilities is so vague, I mean, anything can have happened", adding: "Whether [the authorities] are complicit in a terrorist act, I'm not in a position to comment".
A source close to the Government accused Anwar of attempting to exploit the tragedy for political gain. "The international media response, completely condemning Malaysia, is unfair. It's been partly orchestrated by Malaysia's Opposition," the source said. "The situation is unprecedented. And the search has actually been handled well.
Malaysian authorities did not respond officially to requests for comment on Anwar's accusations, but have previously accused him of politicising the crisis.
Anwar was convicted for sodomy, an offence under Malaysian law, for the third time hours before the flight went missing and is currently on bail pending appeal. He claimed the Government moved his court date to stop him standing in provincial elections.
Investigators and media have focused on the plane's pilot, Captain Zaharie Ahmad Shah, a supporter of Anwar's coalition, despite there being no evidence against him.
Reports have claimed that Zaharie was a "fanatic" who could have hijacked the plane in despair at the latest setback to Anwar. Both Anwar and Zaharie's family have strongly denied any such possibility.
"If you say or suggest that the pilot may have been involved, what about the concealing [of information]? He could not have concealed the radar readings. He could not have instructed the air force to remain completely silent."
Anwar said he'd had several exchanges with Zaharie who was "nice, smart, articulate, but there was clearly a strong passion for justice".
The disappearance of MH370 has put the Government under unprecedented international scrutiny, with persistent criticism that the release of official information has been inaccurate and inconsistent. Anwar said an international committee should be set up from countries whose nationals were among the passengers.
