There has been a twist in the tale of the takeover of Associated British Ports (ABP), as a second offer has sparked a bidding war for the ports operator.

A consortium headed by Australian firm Macquarie has made an offer of 840p a share, matching an earlier bid by a group led by Goldman Sachs.

ABP, which runs 21 British ports, is valued valued at £2.58bn by the bids. ABP, having agreed to back the Goldman Sachs bid, is now being forced to consider the alternative.

The Goldman Sachs-led consortium upped its offer from 810p to 840p a share in anticipation of a counter-bid.

However, analysts believe that bidders will need to go higher to secure a purchase. "We believe that AB Ports is worth up to 860p a share, but in a contested situation could we get to nine pounds," John Lawson, an analyst at Investec, told Reuters.