Workers at one of Singapore's major container terminals are to be tested for Covid-19 after the facility became the site for the city-state's latest virus cluster.

The Covid-19 cluster involved four port workers that were working at PSA International’s Pasir Panjang Terminal, according to Singapore's Ministry of Health (MOH).

A PSA spokesman said the company had "stepped up measures to prevent the further spread of virus" while minimising disruptions to port operations.

PSA said three workers were found to have Covid-19 last month with a fourth employee detected earlier this week.