The House Rules Committee set the stage yesterday for the first floor debate in four years on the CIA's covert aid to the rebels in Angola.

The committee granted the 1991 intelligence authorization bill an open rule, as requested by the leadership of the House Intelligence Committee. That makes the bill subject to debate and amendment on any issue when it goes to the House floor, probably next week.

Already, two amendments on Angola are expected, one to restrict the CIA support and the other to cut it off entirely unless President Bush publicly tells Congress it is "important to the national security."

Rebel leader Jonas Savimbi met yesterday with President Bush to discuss cease-fire prospects in the 15-year-old civil war between the ruling Popular Movement for the Liberation of Angola (MPLA), which is backed by the Soviet Union, and Savimbi's U.S.-backed National Union for the Total Independence of Angola (UNITA).

Savimbi later said Bush "reassured me" that U.S. aid would continue until a cease-fire and a "date certain for free and fair elections."

UNITA receives about $60 million in covert aid yearly from the United States, about $30 million of which is for weapons acquisition. Sources say that amount is again contained in a classified annex of the intelligence authorization bill for 1991.

Rep. Mervyn M. Dymally (D-Calif.) told the Rules Committee that he and Reps. Ronald V. Dellums (D-Calif.) and Bill Richardson (D-N.M.) would offer an amendment banning covert military aid unless the president openly affirms its importance.

Savimbi and State Department officials say a cutoff would put UNITA at a disadvantage because Angola's 200,000-member army has a bigger arms stockpile.

Savimbi told a Capitol Hill breakfast that Luanda will "launch another offensive" if U.S. support for him falters. Rep. Dave McCurdy (D-Okla.) expressed optimism, if the support continues, about the chances for a cease-fire by the end of 1990 and multiparty elections by the end of 1991.