It's up to China to decide whether to appreciate its currency, said Japanese scholars in recent interviews with Xinhua.

"From mid- and long-term perspectives, I think the Chinese currency Renminbi (RMB) will inevitably grow stronger, but it takes time," said Eisuke Sakakibara, professor at Waseda University and former vice finance minister.

"I don't think it is right that the U.S. congress pressure China to that end as the appreciation of a currency is a mid- and long-term process," he added.

"It is important that the Chinese government is going to decide how to realize RMB's gradual appreciation," he said.

In reference to Japan's prolonged economic slump, the professor said that it is still not clear whether Japan's economic stagnation was caused by a stronger yen.

In late 1980s, the benchmark Nikkei 225 Average almost hit the 40,000 line and there was a rampant inflation in real estate price, he said.

"But the overfocus on yen's appreciation bred bubbles, whose bursts eventually plunged the economy into recession," he said.

"This is a lesson from Japan," he added.

"The RMB has appreciated by 21 percent since 2005 and the gradual and measured growth of the currency is the right policy for China," Sakakibara said.

"The RMB will beyond all doubt grow even stronger in the future, " he said.

Commenting on the demand of 130 U.S. congressmen for the appreciation of the RMB against the dollar, Takashi Sekiyama, a research fellow of the government-related think tank the Tokyo Foundation, said a strengthened RMB will contribute little to improving the U.S. economic situation.

"The strengthening of the RMB between 2005 and 2008 did not cut the U.S.-China trade deficit, neither did it enhance the international competitiveness of the U.S. enterprises," he said.

"In this respect, the RMB's appreciation will be of little help to industries and businesses or employees in the United States," said the scholar.

"Diplomatic and trade policies of any nation need to be based on its domestic situation, and it is true for China, Japan, and the United States alike," he said.

"I believe it's important to make efforts to understand each other's concerns and pursue a solution acceptable to both sides through constructive dialogue," Sekiyama said.

Appreciation smacks of a sharp rise, he said.

"The RMB, however, does not need to strengthen dramatically, but in a gradual and measured way," he said.

"Resuming the exchange rate adjustment system, which was in place until 2008, is vital for China's stable development," said Sekiyama.