Shares of Aberdeen-based bus and rail giant FirstGroup fell about 14% after US private equity firm Apollo Global Management said it dropped plans to make a takeover bid for FirstGroup after having two approaches turned down.

Apollo did not say why it was abandoning its plans to bid for FirstGroup, which operates Greyhound intercity coaches and school buses in North America as well as rail services in the UK.

FirstGroup said in a stock exchange statement: “The board of FirstGroup plc notes the announcement made by Apollo Global Management, LLC on behalf of certain of its affiliates that it does not intend to make an offer for FirstGroup.

“In recent weeks the board of FirstGroup received two preliminary and highly conditional indicative proposals from Apollo relating to a possible cash offer for the entire issued and to be issued ordinary share capital of FirstGroup.

“Having considered them in detail, the board of FirstGroup concluded that the proposals fundamentally undervalued the company.

“Accordingly, the board of FirstGroup unanimously rejected the proposals.

“The board of FirstGroup continues to believe in the strong prospects for shareholder value creation available to the company.

“FirstGroup will publish its full year results for the year to 31 March 2018 on 31 May and will update the market on the company’s outlook at that time.

“This announcement has been made by FirstGroup without the agreement or approval of Apollo.”