Church officials in the Philippines on Tuesday accused Manila of trying to increase US troop numbers in the country, as it marked the 114th anniversary of its declaration of independence from Spain.

The left-leaning Ecumenical Bishops Forum, composed of dozens of Roman Catholic and Protestant churches, suggested that closer ties between Manila and Washington would only bring more US soldiers to the Philippines.

"The visit of President (Benigno) Aquino to the US this past week was also about the US military deployment in the Philippines, although the president officially denies it," it said in a statement.

It alleged that US forces had recently been allowed to "re-occupy" their former bases at Clark and Subic Bay -- which have already been converted to commercial purposes.

After the Spanish departure from the Philippines the US took possession of the archipelago in turn.

Nowadays surveys consistently show wide pro-US sentiment among ordinary Filipinos, but there are highly-visible, vocally anti-American nationalists and leftists in religious, academic and elite circles.

During his recent trip Aquino sought greater US help to boost the country's defences amid a two-month long standoff between Philippine and Chinese troops over the Scarborough Shoal, a disputed outcrop in the South China Sea.

Both Manila and Beijing still have ships based at the shoal to press their claims to the area. The standoff has also highlighted how poorly-equipped the Philippines is to handle such external challenges.

Beijing is becoming increasingly assertive in pressing its territorial claims in the area, but the bishops' forum dismissed Manila's concerns.

"The Scarborough conflict is only being made an excuse in order for the US to deploy their forces in the Asia-Pacific to protect its economic interest in the region and to counteract its economic rival China's expansionism," it said.

Among the signatories to the statement was Bishop Deogracias Iniguez, the public affairs chief of the country's influential Catholic bishops, who count about 80 percent of Filipinos as followers.

But Roy Lagarde, a media officer of the Catholic Bishops Conference of the Philippines, said Iniguez signed the document in a personal capacity and it did not mean the bishops endorsed his views.

During Aquino's visit to the United States, Obama pledged US support for efforts to upgrade the notoriously antiquated Philippine military and build a "minimum credible defence posture".

Several hundred US special forces have been rotating through the southern Philippines for a decade to train Filipino soldiers to hunt local Islamist militants with ties to the al-Qaeda network.

The US and Philippine militaries also engage in regular joint exercises and US naval ships transit through the country.