All four are trailing in opinion polls in the run up to the May 9 election.

Four Philippine presidential candidates, including retired boxing star Manny Pacquiao, quelled speculation they were withdrawing from the race and said they remained alternative choices to frontrunner Ferdinand Marcos Jr.

Manila city mayor Francisco Domagoso, Senator Panfilo Lacson and former Defence Secretary Norberto Gonzales, in a joint press conference on Sunday, vowed to fight together “any attempt to subvert the true will of the people by pre-emptive manoeuvres or otherwise limit their choices”.

There were many attempts to limit the electorate’s choices to Marcos and Robredo. That’s why we had to do joint press conference) Mr. Lacson said, without identifying who was making such moves.

The candidates said that their campaigns are approaching the time of great momentum.

Each of us will continue with our respective presidential campaigns and strive to be worthy of choices from which our people will select,”they said in a joint statement.

Pacquiao, who was initially expected to join the press conference but did not show up, will also “never withdraw despite the black propaganda initiated by other candidates”, according to his spokesman.

Mr. Marcos – the son and namesake of the country’s late dictator – has retained a clear lead, with Vice President Leni Robredo far behind in second place.