A California congressman said yesterday that the Carter administration next month will announce abandonment of its plan to build stretches of security fencing along the U.S.-Mexico border.

High officials of the Justice Department and the Immigration and Naturalization Service (INS) insisted that the prediction by Rep. Lionel Van Deerlin, a San Diego Democrat, was wrong.

Van Deerlin, however, stuck to his story, saying that the United States and Mexico will jointly announce, about April 15, that the controversial "Tortilla Curtain," as the barrier is called, will not be built.

INS' plans to reinforce existing fences and add some high-security spans -- a total of about 27 miles on the 1,950-mile common border -- have been held up since last fall, when the project became controversial and angered the Mexican government.

INS held up those plans after a fencing material contractor said the new barrier would feature edges sharp enough to amputate toes and fingers of Mexicans attempting to enter the United States illegally.

U.S. officials denied that the fence would harm climbers, but INS Commissioner Leonel Castillo directed redesign of the wire mesh.

Van Deerlin made his announcement yesterday after John McClaren, a staff assistant, talked with a number of Carter administration officials.

McClaren said he and the congressmen were convinced that the United States would shelve the plan because of the controversy it has stirred and because of its adverse impact on U.S. relations with Mexico.