The Nikkei share average took a sharp downturn, relinquishing earlier advances, after President Trump’s speech left investors uncertain about the prospects for a resolution to the Iran conflict.
At 02:16 GMT, the Nikkei had plummeted 1.6 percent to 52,867, having earlier surged as much as 0.97 percent, according to a report from the Reuters news agency.
Meanwhile, the broader Topix index also surrendered its gains, plummeting 0.98 percent to 3,635.18.
This week’s rally, which had been fueled by optimism over a potential de-escalation in the conflict, had followed a dismal March, during which the Nikkei suffered its worst month since the 2008 global financial crisis.