The Bank of Japan on Friday upgraded its economic assessment for the first time in 20 months, citing improvements in exports and inventories.

"Japan's economy still continues to deteriorate as a whole, although the downward pressure from exports and inventories is gradually abating," the central bank said in a monthly report on recent economic and financial developments.

Earlier this month, the government also upwardly revised its overall economic assessment for the first time since the economy fell into recession in November 2000, saying the economy is beginning to show signs of bottoming out.