TOKYO, Dec 15 (Reuters) - Japanese stocks fell to more than a week low on Friday morning, with mobile firms extending a sell-off on concerns of increased competition after Rakuten said it aims to become Japan's fourth wireless carrier.
Taking the cue from weak U.S. stocks overnight, the Nikkei share average declined 0.7 percent to 22,525.77 in midmorning trade after slipping to 22,479.97, the lowest since Dec. 7.
For the week, the Nikkei has fallen 1.4 percent, on track to post the biggest weekly fall in three months.
The information and communication sector slumped 3.1 percent and was the worst performer on the board.
KDDI Corp tumbled as much as 5.3 percent, NTT Docomo skidded 5.4 percent and SoftBank, which has a more diversified business portfolio, shed 2.6 percent. The sell-off was triggered after Rakuten Inc said it was weighing entry into the mobile carrier market, which would set it up to compete with the telecom giants.
On the other hand, heavyweight stocks such as clothing company Fast Retailing Co rose 0.2 percent, while chip equipment makers also gained ground, with Tokyo Electron rising 0.7 percent and Advantest gaining 0.5 percent.
The broader Topix dropped 1.1 percent to 1,788.99. (Reporting by Ayai Tomisawa; Editing by Shri Navaratnam)