The report suggests that Guardiola is reluctant to sign a new deal at Bayern Munich and appears ready to leave the club when his contract expires at the end of the season.
With Van Gaal's deal set to run for another year, it would leave United in a difficult position if they were to move for Guardiola.
Whereas earlier reports have also linked Guardiola with the manager's job at Manchester City, a successful campaign for Manuel Pellegrini will also cast doubt over a move to the Etihad, too.
