Parliament and devolved decision-makers in Scotland, Wales and Northern Ireland should have to ratify any Brexit deal struck by the Government and Brussels, the Welsh Labour leader has said.
Carwyn Jones, the First Minister of Wales, said the UK's decision to vote to leave the European Union showed that "people won't stand for it when they feel disconnected from their politics and from their politicians".
He also called on Labour to unite, "regain our dignity" and treat each other with respect in a conference speech to members which prompted a standing ovation.
He told delegates: "My priorities have been very clear in the wake of the referendum - we have to retain unfettered access to the single market, anything else would be a massive barrier for trade in Wales.
"I believe that each of the four parliaments in the UK should vote to ratify any final deal, to ensure we progress as one and to show that our concerns have been acted upon."
Mr Jones also stressed that the referendum result had raised questions around the issue of free movement which required a response that must be "fair, proportionate and also of course which speaks to our values as an internationalist party".
He issued a rallying cry to the party, telling members "the country needs Labour to get back on its feet - now more than ever."
He said: "A starting point for us must be to regain our dignity in the way we speak to one another and the way that we speak to the world.
"It wasn't that long ago that the Party's priority was anti-poverty policies, but now we're commissioning reports on anti-Semitism. How did that happen in our own party?"
He added: "We have no hope of creating an open, tolerant country if we can't first do the same for our own Party.
"If we really want to shape what post-Brexit Britain looks like, we have to start treating one another with respect."
Meanwhile, shadow Northern Ireland secretary Dave Anderson highlighted the importance of securing the "best possible" Brexit deal for Northern Ireland.
He said Brexit, and the fact that the former Northern Ireland secretary Theresa Villiers had campaigned for the UK to leave the EU, had "given sustenance to those who are determined to break the United Kingdom apart".