NAIROBI, KENYA, NOV. 18 -- The government of Kenya today ordered the expulsion of nine more missionaries, eight of them Americans, in a continuing reaction to a purported coup plot that the United States calls "patently absurd."

The deportation orders, which give the missionaries and their families one week to leave this East African country, were issued six days after seven other American missionaries were expelled.

The expulsions follow the publication here of a letter that appears to link the missionaries with an alleged scheme by the white-supremacist Ku Klux Klan to overthrow the government of President Daniel arap Moi. The American Embassy here has described the plot as "ludicrous," a "hoax" based on a "forgery," and has appealed to Nairobi to explain the facts behind the forgery to the Kenyan people.

Kenya's official reaction to the apparent hoax has seriously strained relations between the two countries. Thus far, however, Kenya, which is regarded as Washington's closest ally in sub-Saharan Africa, has shown no sign of backing away from its highly publicized belief in the authenticity of the plot.

The only evidence behind the alleged coup plot is a purported Ku Klux Klan fund-raising letter written on the stationery of a North Carolina church. The U.S. Embassy said that an "investigation initiated by U.S. government authorities has produced evidence that the 'memorandum' which appeared in the Kenyan press is a forgery."

Interviews in Kenya and the United States indicate that the forged letter grew out of a squabble between American missionaries and a Kenyan-born preacher, David M.S. Kimweli, who lives near Atlanta.

U.S. officials and missionary sources said Kimweli, who raised large amounts of money in the South for missionary efforts he claimed to have organized in Kenya, attracted the seven American missionaries to this country with allegedly false promises about his ministries.

The sources said they believe that when the Kenyan-based American missionaries wrote back to their home churches to discredit Kimweli, he retaliated with a forged letter that named them as Ku Klux Klan operatives.