3 and T-Mobile have signed a deal with manufacturer Nokia Siemens Networks to help improve the reach of 3G mobile broadband services.
Through their Mobile-Broadband-Network (MBNL) joint venture, the two broadband providers remain on course to complete network upgrade work by the end of 2010.
The £400 million deal with Nokia will now cater for the provision of 3G radio network infrastructure, mobile network planning, implementation, optimisation and maintenance.
Graham Baxter, Chief Technology Officer at 3, said partnering with Nokia would help MBNL deliver on its objective of "creating Europe's largest HSDPA network in record timescales, to quickly enable the best customer experience".
Emin Gurdenli, Technical Director at T-Mobile, commented: "As high-speed mobile broadband becomes increasingly adopted for fast, simple internet access wherever you are, network performance becomes an increasingly important competitive differentiator."
T-Mobile's ongoing merger with rival mobile broadband provider Orange is not set to have any impact on the MBNL, according to the firm.