The Senate Foreign Relations Committee yesterday began action on approval of the appointments of President Conant and four other officials after receiving a letter vouching for their loyalty from Secretary of State Dulles.

Conant's nomination, along with that of General Walter Bedell Smith as Under-Secretary of State designate, and Herman Phleger, choice for State Department counsel, will presumably be confirmed today.

The committee yesterday approved Mrs. Oswald B. Lord's nomination to a United Nations committee, and the choice of Winthrop W. Aldrich as British Ambassador.

McCarthy Awaits Action

Dulles proposed the letter of affirmation Wednesday as speedier than the usual FBI investigation. Senator Alexander Wiley, committee chairman, commented that the FBI report procedure was good, but impractical because some field investigations take up to two months.

No new voices were raised in protest against the Conant choice yesterday. Previously, Senator Joseph McCarthy (R. Wis.) claimed that he had received many letters opposing Conant. Although he has been expected to block the appointment from the Senate floor, McCarthy said he would wait and see what action the Committee takes on Conant.

Support of Dulles' move to speed up committee action drew praise from ex-Governor Paul A. Dever. He said yesterday that an FBI probe is unnecessary since Conant, "having been so intimately connected with the development of the atomic bomb has already been more than adequately subjected to a test of his loyalty. Because of this, I see no reason for a delay of his confirmation."