On Monday he announced a competition for architects to submit designs for apartments measuring just 275 to 300 square feet (25.5 to 28 square meters) to address the shortage of homes suitable and affordable for the city's growing population of one- and two-person households.

"People from all over the world want to live in New York City, and we must develop a new, scalable housing model that is safe, affordable and innovative to meet their needs," the mayor said in a statement announcing the "adAPT NYC" competition.

Bloomberg said the city plans to waive zoning requirements at a city-owned lot in the Kips Bay neighbourhood of Manhattan to allow the construction of a building filled with the "micro-units."

They will be about four times the size of a typical prison cell and about one-fortieth the size of the mayor's Upper East Side townhouse.

Officials say there are about 1.8 million one- and two-person households in New York City, but only about a million studio and one-bedroom apartments - a sign, they say, that the city's housing stock has not kept up with its changing demographics.

Young, single New Yorkers in particular can find it hard to find an affordable apartment as demand outstrips supply.

The mayor is calling for proposals over the next two months for a building containing about 80 micro-units, all of which must have kitchens and bathrooms.

Ideally, they should also have "substantial access to light and air to create a sense of openness," according to the competition announcement.

The apartments, once built, will be sold or rented on the open market. The city will not be subsidizing the project. If successful, the pilot project could help usher in a loosening of the city's zoning laws regarding minimum housing size.

Under New York City's zoning regulations, the average apartment size in a new building must be at least 400 square feet (37 square meters), although there are exceptions to the rule.

The mayor said the project is part of his plan to create or preserve 165,000 affordable homes in the city by 2014.

Although the new apartments will be cosy in realtor-speak, they are unlikely to break any size records. One couple paid $150,000 for a 175-square-foot (16-square-meter) studio in Manhattan in 2009, according to the New York Post.

(Editing By Barbara Goldberg and Xavier Briand)

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