Foreigners in Singapore are not allowed to campaign for political causes, said the Singapore Police Force in an advisory to Malaysians working there.

"The Singapore Police Force is aware of calls encouraging overseas Malaysians to support political activities in relation to the upcoming general election in Malaysia, including by Global Bersih.

"Foreigners visiting, working or living in Singapore should not use Singapore as a platform to further their political causes," said the Singaporean police in a statement today.

The Singaporean police said foreigners must abide by the republic's laws, including laws on public assemblies, or face the penalties including the termination of visas or work passes.

"The police will not grant any permits for assemblies organised by or involving non-Singaporeans for the purpose of political or election campaigning.

"The police will take action against any person who organises or participates in an unlawful public assembly," added the Singaporean police.

On March 28, Geneva-based Global Bersih urged Malaysians residing in Thailand, Singapore, Brunei and Indonesia to return to vote in Malaysia during the general election.

Malaysians residing in these countries are not qualified to be postal voters, although it is applicable for Malaysians residing in other countries.

Global Bersih estimated that there are half a million Malaysian citizens residing in Singapore currently.

The group said that its "JomBalikUndi" campaign in 2013 was a massive success in helping a sizeable number of Singapore-based Malaysians to match travel plans and share transport.

"The campaign did not push the agenda of any political party and was welcoming of all Malaysians who wanted to exercise their constitutional right to cast their ballot.

"We call on the relevant authorities, in both Singapore and Malaysia, to recognise Singapore-based Malaysians' right to cast their ballot and to grant them unhindered ingress and egress at immigration checkpoints," said the group.