Ofgem says it will open investigations into six UK energy companies for failing to meet government energy efficiency targets.

BBC: Ofgem to investigate missed energy efficiency targets

And it's sufficiently likely that Ofgem says the government needs to give serious consideration to the case for further measures to secure gas supplies.

BBC: Cooking without gas

If the energy companies do not co-operate with Ofgem's proposals the government says it will force them to using the new legislation.

BBC: Gas ring