The State Department awarded more than $400,000 in contracts to a company tied to Marine Lt. Col. Oliver L. North's secret Nicaraguan contra support network without seeking competitive bids and then inadequately monitored how the money was spent, according to an inspector general's report released yesterday.

In one instance, the report concluded, department officials classified a $276,000 contract as secret to hide that the award had been made without competitive bidding.

But the State Department's

inspector general found no evidence to support allegations that the

company, International Business Communications (IBC), used State Department funds to lobby Congress illegally in support of the administration's Central American policy.

IBC, a public relations firm headed by former Reagan campaign aide Richard R. Miller, acted as one of North's conduits for private funds used to aid the Nicaraguan rebels. Miller and Carl R. (Spitz) Channell, a conservative fund-raiser, have pleaded guilty to conspiring to defraud the government by using tax-deductible donations for contra military activities.

Secretary of State George P. Shultz said yesterday in testimony before the Iran-contra committees that the procurement procedures for the contracts were "very poor." The IBC contracts were awarded by the State Department's Office of Latin America Public Diplomacy, an office set up in 1983 primarily to promote the administration's contra program.

IBC received four contracts between the summer of 1984 and 1986 to arrange news media interviews for contra leaders and others, prepare pamphlets and perform other public relations services.

Frank Gomez, a top IBC officer and former United State Information Agency official, received two other awards totaling nearly $30,000 and another firm he set up received $5,500, the report said. The report suggested that Gomez may have violated conflict-of-interest rules because he negotiated his first award before he retired in 1984 from USIA.

The House recently voted to cut off funding to the public diplomacy office in the fiscal 1988 after some members called the office unnecessary.

But Shultz testified the office is "on the whole a pretty good operation."

Rep. Dante B. Fascell (D-Fla.), a member of the House Iran-contra committee, said yesterday that he was concerned by evidence suggesting that North, while at the National Security Council, secretly directed the office, which had been headed until January 1986 by Otto Reich, now U.S. ambassador to Venezuela.

Reich, in a written response to the inspector general's report, said any technical violations were due to inadequate support from department contracting officials and inadequate staffing.

Fascell, who has been investigating IBC contracts in his role as chairman of the House Foreign Affairs Committee, said he has concluded that North used the public diplomacy office to help IBC while the firm was a vital part of North's secret contra network.

More than $1 million in funds raised by Channell from private individuals was routed through IBC and an offshore account Miller set up. The money was then deposited in a Swiss bank account used by North to aid the contras.

Fascell said that Channell, while he was working with Miller, also was involved in overseeing television advertising campaigns directed at members of Congress opposed to the administration's Central American policies.

Although there is no evidence that State Department funds were used illegally to lobby Congress, Fascell said, department funds were "comingled" with IBC's private contra funds.

"They {IBC} were performing services for the government under somewhat questionable circumstances on one side, and tying it in with privately raised money on the other side . . . ," Fascell said. "This whole tie-in looks like something that needs stronger consideration."