UPDATE 1-SoftBank prepares for telecoms IPO, CEO aims for this year

* CEO says wants to list this year if possible

* Q3 operating profit falls 2.8 pct yr/yr (Recasts with IPO announcement)

TOKYO, Feb 7 (Reuters) - SoftBank Group Corp said on Wednesday that it wants to list its Japanese telecoms unit this year, a move towards completing its transformation from a domestic telecoms upstart into one of the world's biggest technology investors.

SoftBank said it started preparations to list shares of its core Japanese telecoms unit, SoftBank Corp. The company flagged last month that it was considering listing the business, seeking to raise a reported $18 billion.

SoftBank has long relied on its domestic telecoms business, which makes up a third of overall sales but two-thirds of profit, as a stable source of cash that can be diverted to its growing number of investments around the world.

Founder and CEO Masayoshi Son established the more than $93 billion Vision Fund, the world's largest private-equity fund, which has funnelled more than $9 billion into global startups since its inception in 2016, Thomson Reuters data showed.

Separately on Wednesday, the company reported a 2.8 percent fall in third-quarter operating profit, due in part to higher costs. It did not release a forecast for the current business year, saying there were too many uncertain factors.

($1 = 109.1500 yen)

(Reporting by Sam Nussey Editing by Christopher Cushing)