A policy proposal for a one-time automatic lease top-up for ageing Housing Board flats may immediately tackle the issue of declining value once the leases of these flats are up, but it comes with long-term drawbacks, observers said.

Topping the leases of all HDB flats owned by Singapore citizens back up to 99 years once they are 50 years old would be "a handout that is extremely hard to stop", cautioned ERA Realty head of research and consultancy Nicholas Mak.