He told BBC Radio 4's Today programme: "If we don't get a general election, then yes, we will go for a People's Vote".
More than 100 constituency parties submitted motions demanding a second referendum, and leader Jeremy Corbyn said that he would be "bound" by conference's decision on the issue.
The phrasing was decided after a marathon late-night meeting at the conference in Liverpool on Sunday.
"We would vote it down if it didn't meet our tests in order to send the government, if it is still in office, straight back to the negotiating table", he said.
BBC political correspondent Iain Watson said the final wording of any motion would be crucial and that Mr Corbyn would be hoping it did not tie his hands - but that some members would be pushing for a clear commitment to a new referendum.
"We weren't ruling out options and nobody was ruling out Remain".
And after a five-hour long meeting on Sunday night, the party agreed to hold a vote on whether to "keep all options on the table" - which would include a vote on whether to scrap Brexit entirely and remain in the EU.
He acknowledged the debate "may be rumbustious" but said the chance of a general election would offer the opportunity to change the team carrying out the negotiations with Brussels, replacing Theresa May and her ministers.
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Bishop Guo Xijin of Shanghai, head of an underground diocese, was picked up by government agents in March. The Vatican said the provisional agreement is "not political but pastoral".
SHADOW chancellor John McDonnell said a general election would be "the real People's Vote" on Brexit.
A spokesperson for the anti-Brexit People's Vote campaign, commented: "The facts are clear, as John McDonnell himself admits - the motion before Labour conference offers a clear pathway to a People's Vote with the option of staying in the European Union very firmly on the table".
"The leadership knows where the members are and they know where their voters are".
Bookies have slashed the odds of Theresa May winning any upcoming general election - with bookmakers.tv ranking Corbyn at 5/1 to become Prime Minister.
For those pressing for a second referendum, or a People's Vote, the motion was little more than a fudge.
Anti-Brexit supporters demonstrate in the centre of the city, as it hosts the annual Labour Party Conference, in Liverpool, Britain, September 23, 2018. It calls for Britain to leave the EU but remain in the bloc's customs union with "full access" to the EU's huge single market.
A senior pro-EU Conservative lawmaker, Nicky Morgan, said May would have to give ground on trade and customs arrangements with the EU to overcome the biggest hurdle to a withdrawal accord - the prevention of a hard border between the British province of Northern Ireland and Ireland, a member of the EU. They've spent two years backing the Tories' catastrophic Brexit and are even now trying to ignore their own members who want a People's Vote with the option to remain in the EU.
Labour backed the "remain" side during the 2016 referendum but Corbyn's support was lukewarm.