A diving operator in Vanuatu's capital Port Vila says the New Zealand navy visited last year and offered to remove unexploded bombs but were not given authorisation by the Vanuatu Government.
Mike Crawford, a part-owner of scuba diving company Big Blue, says Fabrice Bilandong, one of his experienced divers, found the bombs.
Mr Crawford says the bombs have been there for 70 years and are covered in coral.
He says they are not in the shipping lane, but he had to inform the New Zealand Navy that they were anchoring immediately above the bombs, prompting them to move their ships.
He says on one occasion he found a 44-gallon drum full of live rounds of ammunition.
"After a big cyclone we had it had burst open. It was just full of 50-calibre bullets as if they were brand new. And they were just spilled all over the bottom of the ocean, but they've since been all covered over. And then the bombs, they found one about three years ago and then they found another five. You know they've been there a long time."
Mike Crawford.