Koichi Hamada, one of Prime Minister Shinzo Abe's special advisers, on Friday condemned past governments led by the Democratic Party of Japan for not pressing the Bank of Japan to conduct enough monetary easing steps to fight the country's prolonged deflation.

"The failure of those politicians in general was not bashing the BOJ like now, but not correcting the (BOJ's) wrong policy for a long time," Hamada, who is also professor emeritus of economics at Yale University, told reporters at the Foreign Correspondents' Club of Japan in Tokyo.

He said journalists also did not understand that the country needs a certain level of inflation to pull the economy out of the long economic slump.