The Abu Dhabi Investment Authority (ADIA) is taking a 16.7% stake in a UK energy supplier.

SSE said it was selling the stake in Scotia Gas Networks (SGN) to ADIA for £621m (€694.7m).

The deal is expected to complete this month.

SSE will keep a 33.3% equity stake in SGN, which supplies gas to 6m properties in Scotland and the south of England.

A 50% stake in SGN was taken by SSE in 2005 for £505m.

SSE said that, following completion of the sale, SSE would have an ownership interest in five economically regulated energy networks with an estimated total value of more than £7bn.

A greater proportion of institutional investors are active in infrastructure, and most plan to raise allocations, according to recent research by Âé¶¹Ó³»­ and Âé¶¹Ó³»­ Real Estate.

The latest Âé¶¹Ó³»­ Institutional Infrastructure Survey, , also suggests most investors no longer perceive the asset class to be expensive.