Days after Motorola confirmed that billionaire financier Carl Icahn was to invest in the company, it has announced that it will not endorse his nomination to the board.

The company has urged its shareholders “not to sign any proxy card” they receive from Icahn or his affiliates.

In a proxy sent to regulators late Friday, Moto confirmed it had received notice that Icahn entities were intent on nominating the billionaire to the board at the company’s next AGM on May 7. The proxy read: “The board urges you to not sign any proxy cards sent to you by the Icahn affiliates… Mr. Icahn’s nomination has not been endorsed by your board of directors.”

The company said that it remains unclear as to whether those entities will “solicit proxies or nominate Mr. Icahn” at the meeting.

The company has encouraged shareholders to vote for Moto’s own directors in the letter and to reject other proposals put forward by Mr Icahn. They include a suggestion to recoup bonuses from executives who have not hit their performance targets. Motorola added that the board has decided not to raise chief executive Ed Zander’s salary of $1.5m this year.

The company has struggled to impress in the last two quarters with shares falling almost 30 per cent since October. Analysts have criticised the company for its lacklustre performance and dated portfolio, particularly in 3G handset designs.