WASHINGTON-Entertainer John Lennon has been told by the Board of Immigration Appeals to leave the United States by Sept. 10 or face deportation, the Justice Department said yesterday.

The board dismissed Lennon's petition to delay its decision until the conclusion of pending lawsuits fighting deportation. Lennon's lawyer, Leon Wildes, said an appeal would be filed and it "would be years before the case is resolved."

Lennon, 34, who was a member of the now-disbanded Beatles rock group, is challenging a federal immigration judge's 1973 order requiring him to leave the country because of his conviction in 1968 in Great Britain for possession of marijuana. The drug was hidden in a binoculars case found in his home, officials said.

"We are not unsympathetic to the plight of the respondent and others in a similar situation under the immigration laws, who have committed only one marijuana violation for which a fine was imposed, " the board wrote in a 4-0 decision, with one member not participating.

"Nevertheless," the board continued, "arguments for a change in the law must be addressed to the legislative, rather than the executive branch of government."

The board said that immigration laws provide that an alien convicted under "any law or regulation relating to the illicit possession of or traffic in narcotic drugs or marijuana" may be excluded from the United States.

Lennon is "not eligible for any relief from deportation except voluntary departure, which has been granted to him by the immigration judge," the appeals board wrote. If Lennon fails to leave the country within 60 days from the date of the order, he will be deported, the board ordered.

However, the board and the immigration service's district director for New York, where Lennon lives, has the authority to extend the deadline. Proceedings in Lennon's two pending lawsuits could affect the board order.

The immigration judge ruled that Lennon must leave the country but granted his wife, Yoko Ono, permission to stay in the United States as a permanent resident alien.

In Jon Wiener's book, "Come Together: John Lennon In His Time", the subject of John's deportation was covered extensively, beginning with Chapter 20. Wiener recounts how the Republican Senator Strom Thurmond from South Carolina, a member of the Senate Internal Security Subcommittee of the Judiciary Committee at the time, received a secret memorandum in February 1972 titled "John Lennon." The committee staff had drafted the memorandum which told of John's appearance at the John Sinclair rally in Ann Arbor, and connected John with members of the Chicago Seven, who, the memo claimed, were ready to disrupt the Republican National Convention in August of 1972 in San Diego. The memo read, in part, "(Rennie) Davis and his cohorts intend to use John Lennon as a drawing card to promote their success...This can only inevitably lead to a clash between a controlled mob organized by this group and law enforcement officials in San Diego...If Lennon's visa is terminated it would be a strategic counter-measure."