GM announced 1,800 indefinite layoffs at its Van Nuys, Calif., and Fairfax, Kan., plants in April. An additional 32,000 workers at GM, Ford and Chrysler plants face one-week layoffs next week. The announcements came as new statistics showed that sales of North American-made cars and light trucks fell 19.6 percent in mid-January. Ford, meanwhile, said it is intensifying a search for new sources of money, but that it was not considering the sale of its Mazda stake.

Bank of Boston Corp. reported that it lost $186.7 million in the fourth quarter of last year and said that it plans to cut another 1,000 jobs. For all of 1990, it lost $394.5 million.

Initial jobless claims for state unemployment insurance benefits were a seasonally adjusted 463,000 for the week ended Jan. 12, an increase of 67,000 from the week before, the Labor Department said.

Bethlehem Steel said it and British Steel will study a possible joint venture that could cost 2,000 jobs, mainly at the American firm, and end steelmaking in Bethlehem, Pa. Steelmaking for the new venture would be located at Steelton, Pa.

Exxon and Chevron reported higher earnings due to increased oil prices. Chevron said 1990 earnings rose by about 860 percent; Exxon's rose 8 percent, but if expenses from its 1989 cleanup of the Valdez oil spill and a one-time accounting change are included, earnings rose 43 percent. Fourth-quarter earnings at Exxon tripled. Chevron earned $633 million in the fourth quarter, compared with a loss of $883 million in the same period in 1989.