WM Morrison has agreed to an improved to takeover offer from a US consortium led by Fortress Investment Group, valuing the supermarket chain at £6.7 billion.

Softbank-owned Fortress increased its offer to fend off a possible counter-offer from New York-based Clayton, Dubilier & Rice, which effectively opened the bidding war for Morrisons with its initial approach at the start of last month.

Shares in Morrisons were up 2.45 per cent on the news.