The case in a US federal court in Wisconsin follows a complaint by Nokia to the Federal Trade Commission in January.

Apple is expected to countersue as it has done in a similar battle with Nokia in a Delaware court, but the latest lawsuit will require a huge amount of effort to fend off, according to US reports.

"These patented innovations are important to Nokia's success as they allow improved product performance and design", the Finnish handset maker said.

Nokia has recently announced plans to introduce a range of high-end devices to help regain ground lost in the smartphone market, mainly due to RIM's Blackberry and Apple's iPhone.

The iPhone's share of the market grew 5% to 16% in the first quarter of 2010, while Nokia's share remained static at 39%, according to IDC.

Apple is ramping up its presence in the mobile arena with the introduction of the iPad, recording sales of more than one million units in the first month.

The unexpected demand for iPads in the US forced Apple to delay the release of the device in other parts of the world by a month.

The iPad will now go on sale outside the US at the end of May in nine other countries, including the UK, where pricing will start at £429, which is £30 more than in the US. Pre-ordering online opens on 10 May.

Prices in continental Europe will begin at around £432 at current exchange rates.

This article was first published by Computer Weekly