Nokia has asked courts in the US, UK and Canada to block sales of rival Blackberry smartphones.

It follows a patent dispute between the Finnish company and Blackberry’s parent, Research In Motion (RIM).

Nokia’s action comes two months after an arbitration ruling by the Stockholm Chamber of Commerce in Sweden.

The organisation had been asked to act as an arbitrator in a dispute over RIM’s use of handsets and tablets featuring wireless local area network (WLAN) connections to the internet. All of RIM’s current products use it.

RIM had argued that an earlier licensing deal with Nokia meant it should not have to pay a separate fee for the technologies. However, the tribunal disagreed.

RIM are also fighting several other patent disputes which come at a difficult time for the company as they prepare to launch their Blackberry 10 handsets.

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