When George Githii resigned as editor of Kenya's most powerful publication at the end of April because of "direct editorial interference" by the Aga Khan, he touched off a far-reached debate on the legitimacy of the mainly foreign-owned press in Kenya.

Githii has accused the Aga Khan - spiritual leader of the world's far-flung Ismaili sect of Moslems, one of the world's richest men and the principal shareholder of Kenya's National Group of newspapers - of ordering The National to print editorials written in Paris.

A former personal secretary to President Jomo Kenyatta and one of Africa's most outspoken anti-Communists, Githii made his letter of resignation public in Kenya's locally owned Viva magazine.

Claiming that the Aga Khan has persistently tried to persuade The Nation to adopt a "pro-Arab and anti-Israel line," Githii also charged that in 1974 the Aga Khan forced the paper to retract its support of a popular insurgent parliamentary candidate in favor of the incumbent and tried to withdraw a Nation editorial critical of Charles de Gaulle because, living in Paris, he did not want to offend the French.

The immediate issue over which Githii resigned was his editorials on dissension within Kenya's Bohra community, who like the Ismailis are Shia Moslems of Asian origin. When the Aga Khan ordered his own comments on the situation printed in the Nation as an editorial Githii resigned.

One Nation reporter said the issue goes beyond the newspaper business:

"When you start getting editorials fed from Paris it shows what kind of country this is."

Under Githii, the 17-year-old Nation grew from a fledging into the most influential newspaper in Kenya.

Its 75-year-old competitor, the venerable Standard is entirely owned by the multinational Lonhro (the London Rhodesia Co., and is also being drawn unwillingly into the debate on foreign ownership of the press.

"It's not just that The Nation and Standard are foreign-owned," said one critical local editor, "it's that Lonrho, the Aga Khan and Kenya's Ismaili community can and do use their newspaper monopoly to strengthen their other economic interests."

Lonrho is Kenya's largest trading company, locally led by Jomo Kenyatta's son-in-law, Udi Gacago. It has a particularly strong hold on the motor trade, with exclusive franchises for European and Japanese acrs and trucks.

The Aga Khan has a huge stake in Kenya's booming tourist industry, including a chain of luxurious hotels offering some of the plushest accommodation in Nairobi, the Indian Ocean coast and in the game parks, while his Ismaili followers are Kenya's most influential Asian community with interests in retail and wholesale trade and manufacturing.

According to Githii, who has often written against government control of the press, "Most people think that press freedom has to do only with pressure from the government.There can be pressures from other sources. Owners can be just as bad."

The Aga Khan, however, has a reputation for a farsighted African policy, just a few years ago he sold 49 per cent of his shares in The Nation to Kenyan nationals, and speculation is mounting that he may divert his majority before other provinces of his Kenyan economic empire come under attack.