Philippines Vice-President Teofisto Guingona has vowed not to "fade away" after he left office over policy differences with President Gloria Macapagal Arroyo.

Mr Guingona, who disagreed with the president over the presence in the Philippines of US troops to give anti-terrorist training to the local military, said he would remain a force in Philippines politics.

He will keep his largely ceremonial post as vice-president.

Pursuant to national interest, I shall also assume an active stand on vital issues

Teofisto Guingona

Media speculation is rife that he will become more outspoken about the policies of Mrs Arroyo, who will take over the foreign affairs portfolio until she appoints a replacement.

Mr Guingona, 74, had agreed to step down on Monday, but announced to reporters on Friday that he was leaving immediately.

"Today, I bow out and say farewell as secretary of foreign affairs - farewell, but not fade away," he said.

He said he wanted to play a "constructive" role and would not pick fights with the administration.

Confusion

The president's offices set off confusion in late June when it released a letter from Mrs Arroyo saying she accepted Mr Guingona's resignation as foreign secretary.

Mr Guingona denied he had quit and the presidential spokesman admitted a mistake had been made in issuing the letter, but Mr Guingona later agreed to step down.

A statement from Mrs Arroyo's office on Friday reiterated that no deal had been struck.

"The vice-president resigned as secretary of foreign affairs in view of honest differences of opinion with the president," the statement said.