South Korea's presidential office said Tuesday that a "significant portion" of information contained in reportedly leaked classified Pentagon documents that detail apparent U.S. spying on Seoul are fake, a stance that the allies’ defense chiefs also agreed on in a phone call.

Seoul's announcement comes after top secret U.S. Defense Department documents leaked online reportedly revealed American intelligence-gathering efforts on allies, including South Korea.

In a phone call Tuesday, the South Korean and U.S. defense chiefs agreed that "a significant number of the documents in question were fabricated," the presidential office in Seoul said in a statement.