The board that supervises Radio/TV Martí failed to provide sufficient information to the U.S. Congress about its costs and audience in Cuba, the U.S. Government Accountability Office said Tuesday.

In a strongly worded report, the GAO also recommended that the Broadcasting Board of Governors study “sharing resources” between the Martí stations and the Voice of America’s Latin America division.

The nine-member BBG, based in Washington, supervises all government broadcasters, including the Martís, VOA, Radio Free Europe, Radio Liberty, Radio Free Asia and the Middle East Broadcasting Network.

Established during the Reagan administration to break the Cuban government’s monopoly on information in the island, the Martí stations have long been one of the most controversial parts of the BBG operations. Many critics have long recommended that the stations be shut down altogether or folded into the Spanish-language section of the Voice of America.

The summary of the 18-page GAO report noted that in 2010 the House and Senate appropriations committees ordered the BBG to submit a “strategic plan” for broadcasting to Cuba, including audiences, costs per listener, broadcasting methods and other measurements. But the plan the broadcasting board submitted in August “lacked key information,” the GAO added. “Of the six requirements in the directive, we found BBG’s strategic plan fully addressed one and partially addressed the remaining five.”

The BBG plan argued that it could not estimate its current audience on the island because Cubans live under a dictatorship and often fear admitting that they listen to foreign broadcasts, according to the GAO report.

But GAO noted that from 2003 to 2008, the broadcasting board nevertheless conducted telephone surveys of Cuban households to estimate audience size.

Those surveys indicated that less than 2 percent of Cuban adults in households with land telephone lines acknowledged that they listened to or watched Radio/TV Martí on a weekly basis, the GAO report added.

The BBG argued that the 2008 survey showed a steep drop in the reach of all foreign broadcasters among Cuba audiences compared to previous years, which raised concerns about the validity of the results of that survey.

“As a result, since 2008, BBG has not conducted telephone surveys of Cubans to estimate the audience size of Radio and TV Marti,” the GAO report noted.

The BBG, in a statement Tuesday, said it would follow the recommendation to study sharing Martí resources with VOA, but repeated its argument that it is difficult if not impossible to estimate the size of the Martí audiences in Cuba.

The GAO report added that the BBG also failed to include in its strategic plan an estimate of the effectiveness of Radio/TV Martí’s “various transmission methods in increasing audience size.”

The Cuban government effectively jams TV Martí’s broadcasting but has more problems jamming Radio Martí, especially in areas outside Havana, according to U.S. broadcasting analysts.

TV Martí in recent months has been delivering its programs to Cuba using DVDs and flash memory drives.

The GAO report also noted that BBG had provided GAO investigators with some information that had been requested by Congress, but was not included in the 2011 strategic plan.

As an example, it noted that a 2009 review concluded that a “unified broadcasting plan for Latin America” — which called for coordination between Radio/TV Marti and VOA — was “of strategic importance.”