The Social Insurance Agency is facing difficulty identifying the holders of some 19.75 million, or 38.8 percent, of the roughly 50 million public pension accounts found earlier this year to be left unidentified, agency officials said Dec. 11.

Of them, about 9.45 million accounts could end up staying unidentifiable due to the registration of false names and other reasons, the officials said.

The latest finding, reported to a task force of the ruling Liberal Democratic Party, could deal a blow to the administration of Prime Minister Yasuo Fukuda as the government and ruling parties have pledged to complete the identification of all those records by March 31.