National Grid expects to invest up to £3.8bn ($5.9bn) in its UK and US businesses this financial year.

And more than £1.5bn of that total is earmarked for transmission work in Britain.

In the US, the company plans to invest £1.2bn according to its latest interim management statement.

Earlier this month, National Grid sold New Hampshire distribution firms Granite State Electric and Energy North Natural Gas to Liberty Energy Utilities for $309m.