The 30-year-old Serbian stopper is so important to the reigning Barclays Premier League champions, that his departure would be a major blow to the club.
Vidic has been ruled out for the remainder of the Red Devils' 2011-12 campaign after sustaining a serious knee ligament injury at the start of December, and his absence has struck a severe blow to Sir Alex Ferguson's men, in their bid to defend the title.
"Vidic for Manchester United is like Messi for Barcelona. How could you take him?" Martina told calciomercato.it.
"He's the United captain and a key player for Sir Alex Ferguson. A move next summer is absolutely not an option."
Vidic is under contract at Old Trafford until 2014, but has frequently been linked with a Manchester United exit.
However, his representative insists that the defender remains fully committed to United, and is focused on his rehabilitation.
"The player is only thinking of recovering as soon as possible from his ugly knee injury," Martina concluded.