King Hamad had also said that Syria was "complicit" in the training by providing the Bahrainis with false passports, The Telegraph reports.
He had reportedly made his claims during a meeting with General David Petraeus, the then commander of the allied forces in Iraq, on July 30, 2008.
The paper quoted a US cable sent on August 13, 2008 as saying: "King Hamad related the report that Bahrainis were receiving training from Hizbollah in Lebanon, but admitted he had no definitive proof."
"He also speculated that the Syrian government was complicit, and 'must be' helping these Bahrainis travel without passport verification as tourists. Post has heard versions of this theory from Bahraini officials in the past, but despite our requests the GOB [Government of Bahrain] has been unable to provide convincing evidence," the leaked cable added.
The king had also told General Petraeus that Iran had urged Bahrain to support it, Syria, and insurgents groups like Hamas, Hizballah, Taliban in booting out American forces from the Gulf", adding: "With friends like these, who needs enemies?"
Hizbollah, which is considered a terrorist organisation by Washington, is a Shia Muslim militant group and political party based in Lebanon. The group is backed both by Iran and Syria. (ANI)