The benchmark Nikkei 225 index was up 0.29 percent or 62.61 points at 21,596.96 in early trade, while the broader Topix index was up 0.21 points or 3.24 points at 1,581.64.

Wall Street stocks fell for a second straight session on Monday as investors reassessed the prospects for lower interest rates ahead of key Federal Reserve congressional testimony.

That sent US long-term rates up, prompting the dollar's appreciation against the yen, analysts said.

The dollar changed hands at 108.76 yen in early Asian trade, against 108.75 yen in New York and 108.31 yen in Tokyo on Monday.

Iran on Monday breached a uranium enrichment cap set under a 2015 nuclear deal and warned Europe against taking retaliatory measures, as France decided to send an envoy to Tehran to try to calm tensions.

"The Japanese market is seen without a clear sense of direction with the intensifying tensions in the Middle East weighing on" the both US and Japanese market, Okasan Online Securities said in a commentary.

However, some bargain-hunting purchases, helped by a cheaper yen, are likely supporting the downside of the market, analysts said.

In Tokyo, oil sector shares were higher, with oil refiner Idemitsu Kosan trading up 1.76 percent at 3,175 yen and crude developer Inpex up 0.56 percent at 963.3 yen.

Automakers were among winners, with Honda edging up 0.68 percent to 2,856.5 yen and Toyota up 0.30 percent to 6,909 yen.