Mobile phone maker Nokia has announced plans to move some of the assembly work on its smartphones to Asia.

The changes, which follow a review of smartphone manufacturing operations, will see work switch from factories in Hungary, Mexico and Finland.

Explaining the decision, Nokia executive vice-president Niklas Savander said that shifting device assembly to Asia would allow the handset maker to become more competitive by improving the time to market as the majority of its component suppliers are based in the region.

Nokia said the changes will mean less work will be carried out at the sites in Komarom, Reynosa and Salo. As a result, it expects to reduce its workforce by about 4,000 throughout the year.

The factories will still play a part in the company's operations, although the focus for the remaining staff at the sites will be on smartphone product customisation, serving customers mainly in Europe and the Americas.