UK number one operator Everything Everywhere will auction off some of its 1,800Mhz spectrum next month with the Royal Bank of Scotland likely to oversee the process, reports the Financial Times. The mandate for the sale is expected to be confirmed next week with the sale to follow soon afterwards, according to Financial Times sources.

The operator is required to sell off some of its spectrum by the European competition authorities as part of the conditions of its formation in 2010, when it combined the T-Mobile UK and Orange UK networks. The sale of spectrum needs to take place before Ofcom’s auction of 4G spectrum can occur.

There is likely to be considerable interest from operators and other mobile service providers due to the spectrum being suitable for high-bandwidth data services. As well as the other UK operators, the likes of Apple, BT, Google, Sky and Virgin are likely to be interested in the spectrum, according to one source.

Financial analysts expect the spectrum auction to fetch as much as £400 million although the price depends on Everything Everywhere’s willingness to sell to a rival operator or another mobile service provider for a lower price The annual charge applied to the spectrum is also likely to be a complicating factor.

Everything Everywhere has previously said it will use the proceeds from the spectrum sale to invest in its UK network. In December it pledged to invest more than £1.5 billion as part of its network evolution plan.