* Labour divisions deepen uncertainty weeks before exit date
* Corbyn to hold conference to determine party stance
* Defuses dispute over deputy leader (Adds Thornberry comments)
By Elizabeth Piper and William James
BRIGHTON, England, Sept 22 (Reuters) - British opposition Labour leader Jeremy Corbyn said on Sunday his party would guide him on how to campaign in a second Brexit referendum, pledging to offer voters a choice between staying in the European Union and a "credible" deal.
At the start of Labour's annual conference in the English seaside resort of Brighton, Corbyn was under renewed pressure from party members and even some of his top team to unequivocally back remaining in the EU in any new vote.
But so far the Labour leader, a leftist who is an instinctive critic of the EU, has struck a neutral stance, saying it was more important to hold the party together by embracing its "remainers" and those who want to leave the bloc.
Just weeks before Prime Minister Boris Johnson has vowed to leave the EU "do or die", Labour, like the governing Conservatives, is deeply divided over Brexit, increasing the uncertainty over Britain's departure, the country's biggest trade and foreign policy decision for more than 40 years.
On the eve of a conference when party officials hoped to present Labour as a government in waiting, a new row broke out when an ally of Corbyn tried to oust deputy leader Tom Watson over Brexit. Corbyn stepped in to defuse the stand-off.
He again appealed to his party to understand that while many of them wanted to remain in the EU, there was a "significant minority" that backed leaving, and so both needed to have an option if it came to a second referendum.
Asked whether Labour would campaign to remain in the EU or to leave with a deal, Corbyn told the BBC he would stage a special conference to determine his party's stance after an election which is widely expected to come before the year-end.
"I am leading the party, I am proud to lead the party, I am proud of the democracy of the party and of course I will go along with whatever decision the party comes to," Corbyn said.
"We will put both views to the British people and say look this is the best deal we could get, (and) this is the remain and hopefully the reform option."
But his foreign affairs policy chief, Emily Thornberry, urged Labour to decide now its stance in a new referendum, voicing growing fears that having an unclear position on Brexit might punish Labour at an election.