* Nikkei dips 0.21%, Topix inches up 0.04%
* U.S.-Iran tensions, stronger yen weigh on Nikkei
* But selling limited ahead of Trump-Xi meeting at upcoming G20
By Shinichi Saoshiro
TOKYO, June 25 (Reuters) - Japan's Nikkei share average edged down on Tuesday amid brewing U.S.-Iran tensions and with a stronger yen weighing on exporters, but losses were limited ahead of a G20 summit, which could determine near-term risk appetite direction.
The Nikkei ended the morning session down 0.21% at 21,241.28.
U.S. President Donald Trump and Chinese Xi Jinping are expected to discuss trade issues on the sidelines of the June 28-29 G20 summit in Japan.
The meeting is the first face-to-face meeting for the leaders since trade talks broke down in May, leading to a hike in U.S. tariffs on imports of Chinese goods.
"It's a quiet market in which sellers are few and sparse ahead of the Trump-Xi meeting at the G20," said Takashi Hiroki, chief strategist at Monex Securities.
"A major breakthrough in trade talks is unlikely but the United States and China might agree to keep the dialogue going at the G20. That could be enough to fuel 'risk on'," he added.
Shares of exporting companies sagged as the yen added to its gains against the dollar.
Toyota Motor Corp dipped 0.2%, Honda Motor Co lost 0.5% and Tokyo Electron fell 1.9%.
Ichibanya Co rallied 5.7% after the curry restaurant chain operator said its operating profit for the March-May period rose 40.7%.
Japan Communications Inc surged 7.3% after the provider of mobile communications services said it will begin sales of SIMs for citizen broadband radio services (CBRS) in the United States.
Of Tokyo's 33 sub-indexes, 20 were in positive territory.
Gainers outnumbered declining shares 1,173 to 852.
The broader Topix edged up 0.04% to 1,548.32. (Editing by Sam Holmes)