The yen is on a roll.

After starting the year at about 120 per dollar, the Japanese currency surged as high as 107.63 early on Monday to its strongest level since October 2014, when the central bank unexpectedly boosted quantitative easing.

But the yen may have even more room to advance this year, argues the man nicknamed "Mr. Yen" for his ability to influence the exchange rate in the 1990s.

Eisuke Sakakibara, the former Finance Ministry official who was in charge of currency intervention in Japan and who is referred to as Mr. Yen, said in an interview with Bloomberg that the currency may appreciate to 105 in the next few months and could get to 100 by year-end.

A yen at 105 per dollar is "no problem" for Japan's economy, he argued, adding that any currency intervention could be done only with agreement from the US and other counterparties.

But not everyone shares Sakakibara's bullish outlook. According to the median of forecasts compiled by Bloomberg, analysts expect the yen to weaken to 118 this year.

Still, for what it's worth, Sakakibara correctly predicted the yen's current rally earlier this year.

And last month he argued in an interview with Bloomberg that the yen's appreciation wasn't "the result of monetary policy or because Japan's recovery is strong," but rather because "the world economy has become very disorderly."

"The problems in the Chinese economy won't be so easy to sort out, and global growth is stagnating," he added. "In that environment, the yen will necessarily strengthen. We're in the first phase of that now."

Investing.com

The yen has remained strong despite various comments from Japanese officials.

On Monday, Bank of Japan Governor Haruhiko Kuroda reiterated his readiness to expand monetary policy further, adding that the central bank would keep a watch on market moves.