It seems that Microsoft is now fighting authorities on both sides of the Atlantic.

The computing giant is currently appealing a £680.9 million EU fine handed down on it in an antitrust case.

But it is now facing further criticism for anti-competitive behaviour in the US.

Officials claimed that Microsoft has been slow to act on demands made from it after a court case in the States when the computing giant was found guilt of abusing its dominance in personal computer operating systems - a case mirroring action being taken by the EU.

Following on from the 2001 case, Microsoft was ordered to issue licenses for companies who want to write programs for the Windows computer operating system, and also provide technical information about Windows to help make the programs work.

But officials claim, in particular, that Microsoft has been dragging its heels when it comes to resolving technical information problems, known as "technical document issues" or TDIs.

"It's clear that the TDIs are not declining", said Jay Himes, chief of the New York attorney general's antitrust bureau.

Himes estimated that each Microsoft employee working on the problems cleared one per month.

But Microsoft promises the issue will be resolved.

A full compliance hearing has been set for 25 September.