Japan finance minister says deeply concerned about yen rise, vows urgent response

TOKYO (Reuters) - Japanese Finance Minister Taro Aso on Friday fired off a warning shot against a recent rise in the yen, saying he was deeply concerned about "one-sided, rapid and speculative" currency moves and would respond urgently if necessary - a hint at possible yen-selling market intervention.

The latest jawboning - official comment intended to influence markets - comes as the yen surged across the board after the Bank of Japan (BOJ) left monetary policy unchanged on Thursday, despite market fears of global turmoil if Britain votes to exit the European Union in the June 23 referendum.

Senior officials from the Ministry of Finance (MOF), the BOJ and the Financial Services Agency (FSA) later held a regular meeting to discuss financial markets. They did not debate contingency plans to counter a market rout in the event of Brexit.

Masatsugu Asakawa, Japan's top currency official, told reporters after the meeting that the officials agreed that volatility in the currency market was increasing and they should liaise closely.In Japan the MOF has jurisdiction over currency policy and intervention. The BOJ conducts intervention under instructions from the ministry.

"Stability in currencies is extremely important. We'll closely coordinate with other countries on this issue," Aso said earlier, adding that he was watching the market with a sense of urgency to prevent speculative moves from persisting.

"We will respond more than ever when necessary. I believe such response is in line with G7 and G20 agreements."

Japan has stayed out from the market since it last intervened in November 2011.

Aso declined to comment when asked if the MOF and FSA have any contingency plans to avoid financial market turmoil in case of Brexit. "It is desirable for Britain to stay in a strong EU," he said.

Asakawa would not be drawn on Brexit contingency measures either. "It is up to Britain whether a Brexit will happen. We did not necessarily discuss concrete responses on the basis of hypothetical situations."

(Reporting by Tetsushi Kajimoto; Editing by Chris Gallagher and Eric Meijer)