The Treasury Department has agreed to change its rules to permit the delivery of Cuban newspapers, magazines and other publications to individual American subscribers without forcing them to get a license.

The same steps are being taken to permit "single issue" subscriptions to Vietnamese, Cambodian and North Korean publications, which have been subject to the same restrictions as those from Cuba.

The government's old rules requiring a license for materials imported from Cuba were first applied last May when thousands of copies of publications began stacking up in Boston, apparently as the result of postal routing.

Customs service inspectors started impounding the documents under a 1917 law barring trade with designated foreign countries during a period of national emergency. The American Civil Liberties Union and the New York-based Center for Constitutional Rights then filed suit in U.S. District Court in Boston charging violation of First Amendment rights.

The ACLU estimated that about 2,000 Americans had been regularly receiving the Cuban publications.

The Justice Department was expected to file its answer in the court case in Boston yesterday. Instead, it asked for more time and the Treasury Department's Office of Foreign Assets Control simultaneously announced new instructions to the U.S. Customs Service.

The new orders were filed with the Federal Register yesterday. Treasury officials said they would "end the detention by U.S. Customs of single copies of publications and similar materials from Cuba."

In addition, the letter said, "the importation of single copies of such materials by individuals and organizations is henceforth authorized without specific license, whether or not the addressees make payments to a designated foreign country for them."

The Treasury Department had insisted that the American subscriber could not pay for the publications at issue. Exceptions were permitted only for scholars, researchers, journalists or scientists working on projects listed by the National Science Foundation or the Library of Congress.

Justice Department lawyer Steve Hart said the new steps should make the suit "moot."