Nikkei opened 1.20 percent higher Monday. At 9:15 a.m., the 225-issue Nikkei Stock Average was up 172.14 points from Friday at 14,482.11, the highest intraday level since May 29. The broader Topix index of all First Section issues on the Tokyo Stock Exchange was up 13.13 points, or 1.10 percent, at 1, 201.71.