Labour Party civil war 'inevitable' after Jeremy Corbyn win
Civil war within the Labour Party is inevitable following Jeremy Corbyn's election as leader, a former Foreign Office minister has said.
Kim Howells said Labour must reconcile its differences to have a chance of winning the 2020 general election.
Despite Mr Corbyn's landslide win, Mr Howells said winning the votes of the wider electorate is a different matter.
Welsh Labour said: "The party is united in our aim to deliver another Labour government in Wales next year."
Asked how he would respond to recent events if he were still an MP, Mr Howells told BBC Wales' Week in Week Out programme: "I'd be bitterly opposed to the current leadership of the Labour Party.
"I'd be saying things that I believe about the need to win political power and a bunch of old Trotskyites are not going win political power."
The former MP for Pontypridd said Labour has to "start speaking in a language people can understand and convince the electorate".
"There is going to be a civil war inside the parliamentary Labour Party. It's nothing new, it's happened in the past," he added.
"So the party's got to make its mind up - does it really think it's going to win again in the future, with Corbyn as the leader? I don't think so."
However, Welsh Labour's assembly election co-ordinator, Ogmore MP Huw Irranca-Davies, insisted the fight in Wales will not be "the Jeremy show" and First Minister Carwyn Jones will be "right at the front" of the campaign.
Rhondda MP and shadow leader of the House of Commons, Chris Bryant, called for unity in the party.
He said: "There are some people who are really anxious at the moment about whether the Labour party has lost its way and I would just say to them, listen carefully to what Jeremy is saying.
"Don't listen to the wild accusations from people. Just listen carefully to what Jeremy is saying. We are taking about doing politics in a different way and heaven knows it needs a change. The Labour party has always been about change."
Richard Wyn Jones, professor of Welsh Politics at Cardiff University, warned of issues between the opposing Labour party in Westminster and the governing one in Wales.
He said: "Welsh Labour has been running Wales since 1999 and the kinds of pressures that you face when governing are very different from ones the Jeremy Corbyn had to face as, essentially, a campaigning backbench MP. And it's easy to envisage that leading to real tensions.
"Now this may well all end in tears. However, I think there's a really interesting phenomenon here and we need to be very careful before we dismiss it."
- Week In Week Out: Corbyn's Revolution - What Now for Wales? 23 September 22:35 BST, BBC One Wales