* Nikkei moves away from 3-week high
* Toshiba stumbles after trust bank says to sue company
By Ayai Tomisawa
TOKYO, Jan 30 (Reuters) - Japan's Nikkei share average fell on Monday morning after a stronger yen weakened export sentiment, while financial companies tumbled after data showed the US economy grew at a slower-than-expected pace.
The Nikkei dropped 0.8 percent to 19,311.41 in mid-morning trade. Analysts said the market is vulnerable to profit-taking with the benchmark index reaching a more than three-week high last week.
"Negative news from the global market is souring sentiment, but even without it, investors would wait a bit to chase the market higher," said Takuya Takahashi, a strategist at Daiwa Securities. He added that investors are cautiously awaiting the U.S. Federal Reserve's first policy meeting for the year on Friday.
The dollar was down 0.55 percent at 114.43 yen after rising to 115.380 on Friday, its highest since Jan. 20.
U.S. Treasury yields fell on Friday after data showed that U.S. gross domestic product rose at a 1.9 percent annual rate, below the 2.2 percent rise expected by economists and the 3.5 percent growth pace logged in the third quarter.
The yen also found support as investors sought safehaven currencies following immigration curbs by U.S. President Donald Trump, which have heightened concerns that the new president's policies will focus more on protectionism and less on the economy.
Insurers and banking stocks underperformed, with Sompo Holdings falling 1.7 percent, MS&AD Insurance Group Holdings dropping 1.5 percent, Mitsubishi UFJ Financial Group shedding 1.5 percent, Mizuho Financial Group declining 1.4 percent and Sumitomo Mitsui Financial Group stumbling 2.1 percent.
Also souring sentiment in the banking sector were banks' dismal earnings. Japan's top banks posted falls in first-half profit as they struggled in the ultra-low interest rate environment.
Meanwhile, Toshiba Corp tumbled as much as 5.8 percent on reports some trust banks are preparing to sue the company for damages.
The Asahi Shimbun reported that several trust banks are set to sue Toshiba after its share price tanked due to a $1.3 billion accounting scandal that has upended the company.
Mitsubishi UFJ Trust and Banking Corp on Monday said it is preparing to sue Toshiba for 1 billion yen ($8.7 million) in damages after its share price tanked due to the scandal.
The broader Topix dropped 0.7 percent to 1,538.50 and the JPX-Nikkei Index 400 fell 0.8 percent to 13,802.30. (Editing by Sam Holmes)