Tokyo stocks opened marginally higher on Thursday supported by rallies on US key indexes, with investors remaining cautious ahead of the ECB monetary decision.

The benchmark Nikkei 225 index was up just 0.05 percent or 13.77 points at 29,050.33 in early trade, while the broader Topix index was up 0.01 percent or 0.22 points at 1,919.96.