TOKYO (Reuters) - Mitsubishi Motors <7211.T> will recall about 1.2 million 660 cc minicar vehicles sold in Japan due to faulty engine oil seals, a part that prevents engine oil from leaking, the Japanese automaker said on Wednesday.

The move is likely to cost Mitsubishi about 7.5 billion yen ($89.3 million), and the costs have yet to be included in the firm's 2012/13 forecast, the company said in a statement.

No vehicles are affected outside of Japan and no accidents or injuries have been reported, a Mitsubishi spokesman said.

Mitsubishi will recall some Minica and Minicab models, as well as other 660 cc models, sold in Japan between 1996 to 2004.

This is the fourth time Mitsubishi is recalling cars over problematic engine oil seals, with the previous recall happening in March.

Japan's transport ministry said it will conduct on-site inspections and has ordered the automaker to report on improvement measures it has taken by end-March.

The seals could slip off and lead to engine oil leakage, which could halt the engine, the spokesman said.

Mitsubishi said it will add a plate that prevents the seal from slipping off, as well as exchange the seal for a new one in some cases.

($1 = 83.9850 Japanese yen)

(Reporting by Yoko Kubota; Editing by Jeremy Laurence and Muralikumar Anantharaman)