Both patients, a 49-year-old woman and a 65-year-old woman, have received two doses of a Covid-19 vaccine. The 49-year-old is infected with the mutant L452R strain.
They had flown to Hong Kong via the United Arab Emirates on the same flight.
One of them had travelled to Mauritius before arriving here, while the other came from Pakistan.
Health authorities also said there were fewer than five preliminary positive cases.