Dubai World, a Dubai government holding company, filed a lawsuit in the United States this week against the former head of a subsidiary it accuses of fraud costing the United Arab Emirates firm millions of dollars.

This complaint is based on a sinister plan that was orchestrated and carried out by defendant Herve Jaubert, said the court document. The suit was filed on Tuesday.

Jaubert was the chief executive of Dubai World subsidiary Exomos, which was established in 2004 to design and manufacture submarines, Dubai World said in a separate statement.

Dubai World is fully confident that the U.S. court will come to the same conclusion as a Dubai court did in April 2009: that Mr. Jaubert misrepresented his ability to design and build submarines to obtain his position as CEO of Exomos, and then used that position to steal millions of dollars from Dubai World, the firm said in the statement.

The company is accusing him of fraud, theft and related charges linked to his time as CEO of Dubai World subsidiary Exomos, it said, adding that the lawsuit was being filed in Florida because that is where Jaubert had fled to from the United Arab Emirates (UAE).

William Hess, a Florida lawyer representing Jaubert, said the allegations were false.

I think that people are going to find it hard to believe that this multibillion corporation ... was duped by Herve Jaubert and it took them years to figure it out, he said by telephone from Stuart, Florida.

Hess said the lawsuit was little more than a defensive move, following Jaubert's own suit against Dubai World, filed in a Florida state court last week.

Jaubert's suit alleges Dubai World made promises that it did not keep in addition to false imprisonment, abuse of process and defamation.

Jaubert currently lives in the United States and is about to publish a book, Escape From Dubai, about his time at Exomos. (http://escapefromdubai.com).

Dubai, one of seven emirates in the UAE federation, has been hit badly by the financial crisis with many government and private sector firms facing financial straits.

Dubai World in June hired AlixPartners, turnaround experts advising on General Motors' bankruptcy, to help restructure the group as it faces $59 billion in liabilities.

(Writing by Raissa Kasolowsky; editing by Karen Foster)