The long career of Rep. Morris K. Udall, one of the Democratic Party's most prominent and eloquent liberals, is nearing an end.

Associates of the ailing Arizona Democrat said Monday he could resign from the House within days.The 68-year-old congressman is disabled by Parkinson's disease and the effects of a fall in which he suffered a concussion, broken ribs and a broken shoulder blade. He has been hospitalized since Jan. 6.

Udall has served in the House since 1961, when he won the seat vacated by his brother Stewart, who became secretary of the interior in President Kennedy's Cabinet.

"There are things that are moving," Stewart Udall said Monday in a telephone interview from Santa Fe, N.M., where he now lives.

Sources in Washington said Norma Udall, the congressman's wife, and Matt James, his top aide, would meet with the counsel for the House this week to discuss the situation. Involved will be retirement options for Udall, who is chairman of the House Interior and Insular Affairs Committee.

The sources, who spoke on condi- tion of anonymity, said a resignation could occur by the end of the week.

"It's moving pretty fast," said one source. "Norma's about to agree to the resignation."

The Phoenix Gazette quoted Mrs. Udall as saying, "It will be an honorable ending for an honorable man's career whenever that time comes. This is a very difficult period for everybody."

Earlier published reports said Mrs. Udall was resisting suggestions that he resign his House seat, a position that put her in conflict with other members of his family.

"These news stories that indicated family divisions are exaggerated," said Stewart Udall.

Nevertheless, Udall's children are known to have retained an attorney to represent their interests.