The federal government will lift its ban on blood donations by Haitians and intensify efforts to screen heterosexuals who pose a risk of transmitting AIDS, a spokesman said yesterday.

"The strengthened program will enhance, rather than replace, the current procedures used to safeguard the blood supply," Health and Human Services Secretary Louis W. Sullivan said. The changes will be phased in by the Food and Drug Administration, an HHS agency.

"By shifting the focus of screening procedures to cover a broader range of risk factors, FDA will build upon the safety of the blood supply while providing all healthy and willing individuals the opportunity to donate blood," Sullivan said.

In place of the ban, all prospective blood donors will be required to answer written and oral questions about high-risk behavior. Prospective donors will be asked whether in the last 12 months they have had syphilis, gonorrhea or hepatitis; traded money or drugs for sex; been paid for sex. About 9 million people give blood each year.

Haitians protested that the ban was discriminatory, and an advisory panel last spring said the policy should be ended. HHS spokesman Brad Stone said the rescission follows the work of the blood products advisory committee.

HHS also will ease the ban on blood donations by black Africans where testing for the form of the AIDS virus found in sub-Saharan Africa is available.

"The most important thing they need to do now is remove the stigma," said Jean-Claude Compas, a Brooklyn, N.Y., a physician and chairman of the Haitian Coalition on AIDS.

"Almost every single medical book in this country has Haitians associated with AIDS," he said, even though there is no association between any disease and national origin.

"It was very traumatic to Haitians and particularly to Haitian youngsters," said Joseph Etienne, director of the Haitian Center Council in Queens, N.Y. He said the FDA informed him of the decision yesterday morning.

Etienne said New York and Miami have the largest populations of Haitian emigres in the United States at 400,000 and 100,000 respectively.

The ban was imposed early in the epidemic because scientists said then they had found high numbers of AIDS cases transmitted by heterosexual contact among Haitians.

All donated blood is tested for the AIDS virus before it is used. However, an infected person may not test positive for six months after contracting the virus.