On the up: National Power

NATIONAL Power shares surged 13 per cent on rumours that the electricity generator - or at least its international unit, - could be the target of AES Corp, the US power plant developer. National Power has denied for months that it is in takeover talks, ever since the April resignation of chief executive Keith Henry on shareholder demands that the utility shift its strategy away from international operations to fuel dividend growth from its domestic business.

"There are three scenarios - a full bid, a demerger of its domestic and foreign businesses, and, more likely, a bid for its international businesses," said Nigel Hawkins, a Williams de Broe analyst: he valued the international assets at pounds 2bn.