TOKYO, June 23 (Reuters) - Japan's Nikkei index fell to a one-week low on Tuesday, after a strong rally that took it to consecutive record highs, prompting investors to take profits.

The Nikkei index fell 3.6 percent to 69,788.38 points, its lowest level in a week, closing below the 70,000-point mark for the first time since last Wednesday.

The broader Topix index fell 2.6 percent to 3990.38 points.

This decline follows a strong rally driven by sustained buying in artificial intelligence and semiconductor stocks, which pushed the Nikkei index above the 72,000-point mark for the first time on Monday, just two sessions after breaking through the 71,000-point barrier.

"After a series of gains, the market appears to be experiencing some profit-taking," said Masahiro Ichikawa, senior market analyst at Sumitomo Mitsui DS Asset Management.

On the Nikkei 225 index, 184 stocks declined compared to 41 that rose.

AI-related stocks, which had been the main driver of the recent market rally, led the losses ahead of Micron Technology's earnings announcement.

Shares of memory chip maker Kioxia plunged 15.1 percent, and shares of technology investor SoftBank Group fell 10.1 percent, while shares of cable and optical fiber maker Fujikura rose 5.3 percent.

Other losing stocks included Furukawa Electric, a cable and component manufacturer, which plunged 15.5 percent, and Mitsui Kenzoku, a non-ferrous metal producer, which fell 12.6 percent.

Among the stocks that posted the biggest percentage gains were Meiji Holdings, which specializes in dairy and confectionery products, and rose 3.5 percent, and Nichiri, which specializes in logistics services, and climbed 3.1 percent.