National Express has been granted another extension to the deadline by which it must make a firm offer for Perth-based transport firm Stagecoach Group — this time to December 14.

Stagecoach said on Tuesday that reciprocal due diligence “is now at an advanced stage and constructive discussions between Stagecoach and National Express are ongoing.”

The Perth firm said the boards of Stagecoach and National Express “continue to believe that the potential combination would be a strategically compelling proposition delivering strong value creation for both sets of shareholders.”

National Express announced on September 21 it was in talks to buy Stagecoach in an all-share deal that would value the Scottish company at about £445 million.

Under the terms of the potential combination, it is expected that Stagecoach shareholders would receive 0.36 new National Express ordinary shares for each Stagecoach ordinary share, resulting in them owning approximately 25% of the combined group.

Stagecoach founders Brian Souter and his sister Ann Gloag announced in April a 10-year plan to reduce their shareholdings in the firm from 27% to 5% — a move that some analysts viewed as paving the way for a takeover.

On Tuesday, Stagecoach said in a stock exchange statement: “On 21 September 2021, Stagecoach Group plc and National Express Group PLC announced that they were in discussions in relation to a possible all-share combination.

“As announced on 18 October 2021, in accordance with Rule 2.6(a) of the Code, National Express is required, by not later than 5.00 p.m. (London time) on 16 November 2021, either to announce a firm intention to make an offer for Stagecoach in accordance with Rule 2.7 of the Code or to announce that it does not intend to make an offer for Stagecoach.

“Reciprocal due diligence is now at an advanced stage and constructive discussions between Stagecoach and National Express are ongoing.

“The boards of Stagecoach and National Express continue to believe that the potential combination would be a strategically compelling proposition delivering strong value creation for both sets of shareholders.

“In light of the above, and in accordance with Rule 2.6(c) of the Code, the board of Stagecoach has requested, and the Panel on Takeovers and Mergers (the Takeover Panel) has consented to, an extension to the date by which National Express is required either to announce a firm intention to make an offer for Stagecoach in accordance with Rule 2.7 of the Code or to announce that it does not intend to make an offer, in which case the announcement will be treated as a statement to which Rule 2.8 of the Code applies.

“Such announcement must now be made by not later than 5.00 p.m. (London time) on 14 December 2021.

“This deadline can be extended by the board of Stagecoach, with the consent of the Takeover Panel, in accordance with Rule 2.6(c) of the Code.

“As noted above, discussions between the parties remain ongoing and there can be no certainty that an offer will be made.

“A further announcement will be made as and when appropriate.”