(Adds MFE comment)

BERLIN/MILAN, March 28 (Reuters) - ProSiebenSat.1 said on Monday that MediaForEurope (MFE) had rejected the offer of a seat on the supervisory board of the German broadcaster, suggesting that no compromise has been reached with its top investor ahead of a May shareholder vote.

MFE , which is controlled by the family of former Italian Prime Minister Silvio Berlusconi, has called for closer cooperation with Munich-based ProSieben, in which it has a voting stake of more than 25%.

The Milan-listed group has also asked ProSieben to engage in talks over strategy, focusing on its core TV business.

ProSieben said in December that it was extending CEO Rainer Beaujean's contract until 2027, and the supervisory board intended to propose Andreas Wiele, a former Axel Springer executive board member, as its new chairman.

MFE was not given advance notice of this plan and it was not involved either in the decision to propose former RTL boss Bert Habets and Rolf Nonnenmacher for other two seats that are to be reallocated at ProSieben's annual general meeting on May 5.

ProSieben said in a statement on Monday that its supervisory board unanimously approved the proposals, which were the result of a comprehensive selection process initiated in mid-2021.

It said it had also offered MFE the opportunity to propose its own candidate, in return for supporting the supervisory board candidates.

"MFE-MediaForEurope rejected this proposal, which the supervisory board very much regrets", it said.

MFE does not have any supervisory board representatives but has reserved the right to present rival candidates by April 20.

"MFE has absolutely no interest in controversy. Our position will be presented at the appropriate time... and in the interests of the company and all its shareholders", a spokesperson for MFE said.

A source familiar with the matter said MFE's own board of directors could be updated on the developments at a meeting scheduled for Tuesday.

Formerly known as Mediaset, MFE sees building a continental TV champion as the answer to challenges posed by streaming giants and online advertising platforms.

For its part, German TV group ProSieben has been pursuing a standalone strategy, while investing in tech businesses, such as e-commerce operations and online dating platform ParshipMeet. (Reporting by Alexander Huebner and Elvira Pollina; Writing by Miranda Murray; Editing by Thomas Escritt, Keith Weir and Alexander Smith)