(Adds Corbyn comment, opinion poll)
By Costas Pitas and Elizabeth Piper
LONDON/ BRIGHTON, England, Sept 21 (Reuters) - The deputy leader of Britain's Labour Party survived an attempt to oust him over Brexit on Saturday after party chief Jeremy Corbyn moved to defuse a row that threatened to overshadow the party's bid to show it was ready for power.
Holding its annual party conference just weeks before Prime Minister Boris Johnson has promised "do or die" to lead Britain out of the European Union, Labour was keen to set out its agenda for government rather than put its Brexit divisions on display.
But a move by Corbyn ally Jon Lansman, founder of the left-wing grassroots movement Momentum, to propose a motion to abolish the deputy's post because of disloyalty over Brexit threatened to derail those plans.
The attempt underlined the deep divisions in Britain's main opposition party over Brexit, rifts that have also fractured the governing Conservative Party and have cast doubt over when, how or whether Brexit will take place on Oct. 31.
Deputy leader Tom Watson, who has often criticised Corbyn, described the attempt as "a drive-by shooting" after he challenged the Labour leader's position on Brexit and suggested a second referendum should be held before any new election.
A Labour source said Corbyn, who backs an election first, had intervened just as the party gathered for the annual conference in the seaside resort of Brighton.
"Jeremy Corbyn proposed that the motion not go to a vote and instead that there be a review of the position of deputy leader and other positions in support of the leader," the source said.
The motion, which appeared to blindside Corbyn's team, had provoked criticism from Labour figures, including London Mayor Sadiq Khan, as Britain heads towards a possible parliamentary election to unlock the Brexit impasse.
"We must focus on fighting against Boris Johnson & his catastrophic no-deal Brexit, not each other," Khan tweeted.
An opinion poll on Saturday showed Labour trailing the Conservatives 22% to 37%.
Britain's decision to back leaving the EU in a 2016 referendum has divided not only the country's main political parties, but its towns and cities and often families. More than three years on, little is clear on how Brexit will happen.
Johnson has said he will take Britain out of the bloc on Oct. 31 with or without a deal to smooth the country's biggest trade and foreign policy shift for more than 40 years.
Labour, and other opposition parties, have tried to prevent him from being able to stage a potentially damaging no-deal Brexit, refusing to back his call for a new election until the prospect of leaving without an agreement is taken off the table.
Labour said in a draft statement on Brexit that if the party won power, it would "get Brexit sorted one way or another within six months of coming to power".
The statement, yet to be agreed at the conference in Brighton, sets out that a Labour government would "secure a sensible leave deal with the EU within three months, and within six months would put it before the people in a referendum alongside the option to remain."
The Mirror newspaper late on Saturday cited Corbyn as saying a public vote would happen in June were Labour to win an election this year but he declined to say how he would vote. "I'll let you know at the time," he said. (Reporting by Costas Pitas and Elizabeth Piper, Editing by Giles Elgood and Rosalba O'Brien)