London "Ghost Luxury Apartments" Growing

I've just read an article in Singapore's Business Times about mounting concern over the growing market of London Ghost property.
The trend is tagged "buy-to-leave" and is in a nutshell driven by foreign real estate buyers speculating on capital appreciation of upscale London apartments.
While a mounting segment of end-users are scrambling with find rentals, a legion of properties are being kept vacant for longer-term flipping.
There is pressure on local-government authorities to place restrictions on owners to either occupy or else rent out their units.
Over the past three to four years Phuket has experienced a ramp up of small cheap apartments and it's likely that supply and demand will see the island have it's very own 'buy-to-leave' issue in the short term once these projects complete and handover.