Shares in Dutch construction group Ballast Nedam rose over 20% in early trading in Amsterdam on Wednesday after the company said it had been approached by ‘certain Dutch and international parties’ about a merger or takeover.

Ballast Nedam said the companies, which it did not name, wanted to look at the options together.

‘Ballast Nedam always gives strategic options serious consideration in the interests of its shareholders and other stakeholders,’ the company said in a short statement.

Further announcements will be made when ‘appropriate or necessary’.

Ballast Nedam also said on Wednesday it had completed the sale of its offshore activities to Van Oord which will deliver a ‘substantial’ book profit for 2014.