UPDATE 1-United Tech to sell Pratt power systems unit to Mitsubishi Heavy

Dec 12 (Reuters) - United Technologies Corp, the world's largest maker of elevators and air conditioners, said it will sell the power systems business of its aircraft engine unit, Pratt & Whitney, to Mitsubishi Heavy Industries.

The power systems unit makes industrial gas turbines and geothermal power systems based on Pratt & Whitney's aircraft engine technology.

"Divesting Power Systems allows UTC to focus on its core aerospace and commercial businesses," United Technologies said on Wednesday.

The company did not disclose the terms of the deal, which is expected to close in the second quarter of 2013.

Reuters reported in June that the company was looking to sell the business for about $1 billion.

United Technologies reported in October a 3 percent decline in third-quarter earnings and cut its sales forecast for the year, citing weak demand from airlines and an uncertain economy.

Shares of the company, which also owns Otis elevators and escalators and helicopter maker Sikorsky, closed at $81.19 on the New York Stock Exchange on Tuesday.