The informed defense source denied the claim after the US Navy said earlier in the day that Iran had attempted to seize two tankers near the Hormuz Strait.
The Iranian source did not provide further details, according to Iranian media.
Earlier on Wednesday, a US military statement claimed it had blocked two attempts by the Iranian Navy to seize commercial tankers in international waters off Oman.
The Iranian Navy sought to seize the Marshall Islands-flagged TRF Moss and hours later the Bahamian-flagged Richmond Voyager, in both cases fleeing after a US destroyer appeared on the scene, the US Central Command said in a statement.
The statement claimed in one case Iranian forces fired shots at the tanker.
Back in April, Iranian forces seized two tankers within a week in the Persian Gulf and the Sea of Oman, one of them over a judicial complaint by a private plaintiff and the other over a maritime accident with an Iranian fishing craft.
Over the past years, the US Navy has several times seized Iranian-controlled tankers and shipments of oil en route to other countries, citing its own sanctions on Iran's oil exports.
Iran says it views US military vessels lurking in the waters of the Persian Gulf as a threat to its security and a source of tensions and instability in the region.
MNA/PressTV