Philippine President Benigno Aquino sought Wednesday to quash rumours that a coup is being plotted against him, with his spokesman insisting he had the military's full support.

A senator-ally of Aquino alleged earlier this week that retired military officials were trying to recruit troops to destabilise the government, but Aquino spokesman Edwin Lacierda downplayed the warning.

"There are no reports of restiveness among the rank and file," Lacierda told reporters.

The Philippines has one of Asia's most vibrant democracies but the military has a long history of interfering in the political process.

It backed dictator Ferdinand Marcos until a people power revolution ended his reign in 1986 that installed Aquino's late mother, Corazon Aquino as president.

The first Aquino president survived a series of bloody coup attempts over the next five years, including a 1987 rising when rebel troops killed three security escorts of her son and future president, who was left with a bullet lodged on his neck.

And he mused in a speech to Congress on Monday night that somebody could try to kill him again in a bid to derail the reforms he has put in place.

"Will there be a day when I go onstage, for work, and -- will someone manage to plant a bomb? Will the dark schemes of those who want to bring us back to the wrong way of doing things finally succeed?" he said.

Independent pollsters say Aquino, one of the most popular presidents the country has known, has seen his approval ratings dip this month amid his quarrel with the Supreme Court over his 2011-2013 economic stimulus programme worth billions of dollars.

The court ruled this month that the programme was illegal because the president neglected to get authorisation from Congress. Aquino has appealed the ruling.

The dispute prompted warnings of a potential constitutional crisis.

Philippine military chief General Gregorio Catapang warned his troops last week not to meddle on the issue.

The coup rumours gathered pace this week after residents saw large numbers of troops in trucks and armoured transports rolling into the capital Manila from a nearby province.

Military spokesman Lieutenant-Colonel Ramon Zagala insisted on Wednesday that these were regular military movements that had nothing to do with destabilisation.

"We apologise for having alarmed our countrymen. These movements are necessary for administrative and logistical support of our troops in the field," he told reporters.

"As far as the active (service) is concerned, (it has) not monitored destabilisation or recruitment or planning within our ranks."

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