Months after American researchers were refused permission to carry out tests off Bermuda they have been given a second embarrassing rebuffal.

The refusal of Mexico to allow the team from the Lamont-Doherty Earth Observatory at Columbia University in New York to do seismic underwater testing because of fears for the safety of marine mammals has left their research schedule is ?disarray,? according to the latest edition of Nature magazine.

The team and their research ship wanted to do similar testing off Bermuda in November but Government said no because of fears it could harm the hearing of dolphins and whales.

The researchers didn?t have permission for the underwater seismic testing when they docked in the Island and were forced to return to the States.

The scientists applied for permission about a month before reaching Bermuda but applications are understood to normally be submitted at least a year in advance.

Now the same thing has happened in February, says Nature, after the Mexican government expressed concern about the possible impact studies on an underwater meteorite crater might have on mammals.

The magazine said a senior official at the National Science Foundation, which oversees the research, described the setbacks as an ?embarrassment?. James Yoder, the director of ocean sciences at the agency, said: ?We are not on top of this. We need to review everything we are doing before we leave the dock.?

The magazine says the aborted research in Bermuda and Mexico has cost around $2.6 million.

It quotes Dr Jack Ward, Bermuda?s Director of Conservation Services, as saying: ?The ship showed up without permission. They didn?t give us anything to work with. It was crazy. It was easy to say no.?

He said Bermuda?s 200 mile territorial waters had been declared a whale sanctuary in July 2000. ?They (Lamont-Doherty) said they wouldn?t have come if they had known that,? said Dr. Ward.

And Marcia McNutt, the director of the Monterey Bay Aquarium Research Institute in California, who was the lead scientist for the Bermuda cruise, described it as ?a huge waste of time and money?.