Owen Smith has said Jeremy Corbyn's proposal that the Labour membership vote for a proportion of the shadow cabinet is about "deepening the divisions that he's created in the party."
Corbyn, on the other hand, has quite a different view.
The Labour leader suffered a number of high profile resignations from his cabinet earlier this year, and Smith sees this as an attempt at getting more people elected to the cabinet that align with Corbyn's - and the membership's - views.
"It's an attempt to further cement his position and to use the membership as a means of driving a wedge between the MPs and his leadership," Smith said.
He added: "If he was serious about trying to unify the party, then he would be taking serious the notion of going back to the traditional method we have had of guaranteeing that there was some balance in the shadow cabinet, and that everybody felt in the party that they had some representation, which was election through the PLP."
Corbyn's election as leader, which looks likely to happen again following the latest vote, has shown that there is a sharp contrast between the Parliamentary Labour Party and its members, with the members highly favouring Corbyn.
The proposed changes were discussed at a meeting of the party's ruling committee on Tuesday, with those hoping to be elected to the cabinet having to gather votes not just from MPs, but also garner the support of members and the leader in a potential three-way split of the electorate.
Tom Watson is due to present alternative plans to reintroduce shadow cabinet elections by MPs - scrapped by Ed Miliband in 2011 - but the deputy leader and other senior MPs remain open to Corbyn's idea.