"The decision by Plymouth Argyle to delay the announcement of their new manager has created an atmosphere of intense uncertainty at a crucial stage of the season," Bonser told the club's official website.
"The situation was created by Colin Lee being prepared to talk to Plymouth Argyle about their managerial vacancy just six months after pledging his long-term future to Walsall.
"The uncertainty that has been caused has had to be dealt with, and I believe this decision to be in the best interests of Walsall."