Guardiola announced his decision to step down at the end of the season last month, citing fatigue as the primary reason for his resignation.
However, Laporta claims that the former Spain international is walking away because he was not given adequate backing from above, something he believes the Barca board swiftly attempted to make amends for by naming current assistant coach Vilanova as his replacement.
"It is a panic decision after not having done more for Guardiola," the former Blaugrana supremo said to Catalunya Radio.
"Barca are in a cycle of change and Guardiola dared not try do so because he did not have enough support from the board.
"I have known the board members for many years and they have a different concept of what the club should be."
Laporta added that Guardiola, who has claimed 13 titles since replacing Frank Rijkaard as coach in the summer of 2008, should always be welcome back at Camp Nou.
"Pep can return whenever he wants, even as president, because he has earned it," the Catalan politician enthused.
Guardiola can end his four-year reign on a high note later this month, with Barca set to take on Athletic Bilbao in the Copa del Rey final on May 25.
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