By Kirk Spitzer

USA TODAY

TOKYO – Japanese officials scrambled Friday to assess the damage from Britain’s stunning vote to leave the European Union.

Japan’s Nikkei 225 index dropped 7.9% in volatile trading following the U.K. vote, closing below 15,000 for the first time in more than four months. That’s the steepest drop in more than 16 years.

Meanwhile, the yen surged, briefly trading below 100 yen to the dollar for the first time since November 2013. That represents another setback for “Abenomics,” which depends in part on a weak yen to boost exports and encourage domestic consumption.

Prime Minister Shinzo Abe said he would take steps to stabilize the markets and scheduled a meeting of his Cabinet for late Friday.

Finance Minister Taro Aso said Japan would consider “currency swaps” as a way to stabilize the yen, and Bank of Japan Gov. Haruhiko Kuroda said he would work with overseas central banks, as well, according to Japan’s Kyodo News service.

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The vote could have effects beyond Japan’s financial markets.

Kyodo News reported that one Cabinet official said that a free trade agreement between Japan and the EU — under negotiation since 2013 — would be difficult to reach this year as a result of the “Brexit" vote.

The EU is one of Japan’s largest trading partners. At the recent G-7 Summit in Ise-Shima, Japan, Abe and leaders of the EU and four major European economies said they hoped to reach agreement on the new trade pact in 2016.

James D.J. Brown, associate professor and academic program coordinator for international affairs at Temple University’s Tokyo campus, said the vote also could impact Japanese manufacturers with headquarters and production facilities in the U.K., including major automakers.

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“If the U.K. loses access to the EU single market, their operations will cease to be profitable. Although it will not happen immediately, these companies may therefore consider shifting their operations to other EU countries, especially in Eastern Europe,” said Brown.

Most polls in recent days predicted a close victory for “remain” supporters and it is not clear if Abe and leaders of the ruling Liberal Democratic Party were prepared for the stunning turnaround.

Abe has been focused in recent weeks on domestic and regional concerns, including a crucial Upper House election set for July 10, North Korea missile launches and intrusions by Chinese warships into or near Japanese territorial waters.