* Toshiba tumbles after asking to delay Q3 earnings filing again
* Mining sector rises 1.9 pct after pacts signed with Saudi Arabia
By Ayai Tomisawa
TOKYO, March 14 (Reuters) - Japanese stocks barely moved on Tuesday ahead of an expected U.S. interest rate hike, though shares in the mining sectors got a boost after Japan and Saudi Arabia signed economic cooperation agreements.
The Nikkei share average shed 0.1 percent to 19,619.14 at the midday break.
With a U.S. rate hike already priced in market expectations, investors are focused on Fed Chair Janet Yellen's speech after the two-day meeting that begins later on Tuesday.
Masayuki Kubota, chief strategist at Rakuten Securities, said the market will focus on whether she "supports constant rate hikes this year or not", adding that Yellen's stance will impact dollar-yen moves.
The mining sector surged 1.9 percent and was the biggest performer on the board, with Inpex Corp rising 2.0 percent and Japan Petroleum Exploration Co gaining 1.4 percent.
On Monday, Japan and Saudi Arabia signed economic cooperation agreements in industry, energy and finance and on setting up a possible special economic zone in Saudi Arabia, and Prime Minister Shinzo Abe asked Saudi Arabia's King Salman to support a listing of oil giant Aramco's shares in Tokyo.
"Investors hope that the two countries' long-term economic cooperations will bring Japanese companies chances for growth," said Hikaru Sato, a senior technical analyst at Daiwa Securities.
Meanwhile, Toshiba Corp spooked investors and dived 7.5 percent after the company said it has asked financial regulators to extend its Tuesday deadline for submitting official third-quarter earnings until April 11.
The broader Topix dropped 0.2 percent to 1,575.06 and the JPX-Nikkei Index 400 shed 0.1 percent to 14.102.30. (Editing by Richard Borsuk)