Kim Dotcom's US lawyer has denied that a guilty plea by one of the Megaupload's former employees has major implications for his client's case.

Andrus Nomm was sentenced to a year in jail after pleading guilty on Friday to conspiracy to commit copyright infringement while working for the now defunct file-sharing site.

The US is currently trying to extradite Mr Dotcom, who founded Megaupload, from New Zealand to stand trial.

Mr Dotcom denies wrongdoing.

The US Department of Justice (DoJ) has alleged that Megaupload's staff had "operated websites that wilfully reproduced and distributed infringing copies of copyrighted works" over a period of five years, causing more than $400m (260m) of harm to copyright owners.

Nomm - a 36-year-old Estonian citizen - agreed to this damages estimate as part of his plea, according to a press release from the DoJ. He had been living in the Netherlands before he travelled to Virginia to make the deal with the US authorities.

The DoJ added that Nomm had acknowledged that through his work as a computer programmer for Megaupload, he had become aware of copyright-infringing material being stored on its sites, including films and TV shows that had contained FBI anti-piracy warnings.

It said he had also admitted to having downloaded copyright-infringing files himself.

"This conviction is a significant step forward in the largest criminal copyright case in US history," said assistant attorney general Leslie Caldwell.

BBC News