Protesters, estimated by an AFP reporter to number around 400, wore black headbands with the words "Protect Singaporean Rights" in red as they chanted slogans against the long-ruling People's Action Party.

Protest leader Gilbert Goh, an employment counsellor, said the rally was intended to display Singaporeans' continued dissatisfaction with the large foreign population in the city-state.

"When we speak up for the country, we are branded as xenophobes, " he told AFP. "I am doing all this for my country, I am willing to die for my country."

Goh, however, dropped plans to ask rally participants to deface a poster of Prime Minister Lee Hsien Loong after receiving a stern warning from the police.

Singaporeans make up just over 60 percent of the country's 5.4 million population. Its low fertility rate forces the island republic to rely heavily on guest workers to power its affluent economy.

The protest took place at a designed free-speech park amid a wave of attacks in social media directed at the Filipino community over a planned festival celebrating Philippine Independence Day in June along busy Orchard Road.

Prime Minister Lee had denounced the abusive anti-Filipino attacks as the work of a few "trolls" and said people who harassed organisers of the planned event were "a disgrace to Singapore".

Protester Richard Lim said at Thursday's rally that Singaporeans remain dissatisfied with the government's immigration policies despite restrictions on the intake of foreign workers and a reduction in the approval of permanent residency applications.

"You take the trains, you will know why we are still angry. Everywhere we go it is crowded. They don't listen to us when we say don't bring in any more foreigners!" said the 57-year-old security guard.

Thursday's rally fell short of protests attended by several thousand people in early 2013 after the government published a policy paper indicating that the government was looking at a future population of 6.9 million.

Critics accuse foreigners of competing with Singaporeans for jobs, housing and medical care as well as choking public transport even though the unemployment rate stands at just over two percent -- one of the lowest figures in the world.