The yen's recent declines have been driven by fundamentals and would be no reason for Japan to change its economic policy, including the central bank's ultra-low interest rates, a senior International Monetary Fund (IMF) official said.

The remarks highlight the difficulty Tokyo may face if it seeks international consent to intervene in the currency market to stem further yen falls, as G7 and G20 countries agree such action is justified only if exchange rates move out of line with fundamentals.

"What we're seeing so far on the yen is driven by fundamentals," Sanjaya Panth, deputy director of the IMF's Asia and Pacific Department, said late on Wednesday.