Shares of Japan's Mitsubishi Motors Corp plunged more than 10% to an all-time low on Tuesday after the automaker posted dismal sales in its key Southeast Asian market and forecast a huge loss for this financial year.

A day earlier, Mitsubishi Motors, a junior member of the auto alliance of Nissan Motor and Renault SA, projected an operating loss of 140 billion yen ($1.33 billion) for the year ending on March 31, 2021, due in part to the coronavirus pandemic.

It would be the automaker's biggest loss in at least 18 years, according to records dating back to 2002.

Mitsubishi Motors' results were "shocking", said analyst Mio Kato of LightStream Research, who publishes on the Smartkarma platform, noting that Southeast Asia was particularly concerning.

"ASEAN was meant to be its growth driver and was even positioned as its key attractive point to the Renault-Nissan Alliance. ASEAN sales have collapsed and it is now generating losses," Kato said in a note to clients, referring to the Southeast Asian region.

Mitsubishi's shares fell more than 10% to 240 yen, marking a lifetime low since their 1988 listing.

The coronavirus crisis has exacerbated struggles at the company, which had already been battling falling sales in China and Southeast Asia, a major market that accounts for a quarter of its sales.

Announcing a restructuring plan on Monday, Mitsubishi Motors said it would stop making the Pajero SUV crossover model next year, and close the plant in Japan that makes it. It also said it would reduce its presence in Europe and North America and focus on growing in Asia.