TOKYO: Tokyo stocks opened flat Tuesday as investors retreated to the sidelines to await the outcome of a US-Japan summit expected to be dominated by trade tensions and North Korea.

The benchmark Nikkei 225 inched up 0.04 percent or 7.89 points to 21,843.42 in early trade, while the broader Topix was down 0.06 percent or 1.03 points at 1,735.19.