A People's Vote campaign spokesman said the conference motion was "clear movement" towards adopting a referendum.
His comments came as a poll found 86% of Labour members think voters should have the final say on the outcome of Brexit negotiations, and 90% would now vote to remain in the EU. The pair opted not to take hospitality seating, showing their socialist values.
Corbyn has long said that a "People's Vote" is not off the table for his party, and a source close to the leadership urged caution over an as-yet unknown motion, repeating the Labour leader's stance that he does not support a second referendum.
Corbyn wanted his conference to be an opportunity to sell his alternative vision for Britain's economy, pressing his argument for the renationalization of rail, mail and utilities, and to rally the party for a possible early election.
"If we are going to respect the referendum it will be about the deal", he said of any so-called People's Vote.
An early draft proposing "a public vote on the terms of Brexit" was rejected in favour of a broader framing of a new referendum, leaving open the possibility of an option to stay in the European Union being on the ballot paper.
"Our preference would be for a general election and we can then negotiate our future relationship with Europe but let's see what comes out of conference", he told the BBC's Andrew Marr Show, saying Labour was ready to vote against any deal.More news: New allegations surfaces over Trump's court nominee
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Despite warnings it would "purge" Labour of MPs from the Blairite tradition that won three elections, delegates in Liverpool slashed the number of local members needed to trigger a challenge to a sitting MP.
With the United Kingdom and the European Union at an impasse in divorce talks, many Labour members think the left-of-center party has the power and a duty to force a new referendum that could reverse Britain's decision to leave the 28-nation bloc.
The phrasing was decided after a marathon late-night meeting at the conference in Liverpool on Sunday. "We must back it if Labour members want it", he told The Observer newspaper. If that does not succeed, then the party should keep all options on the table, including the possibility of a second referendum on a question yet to be determined.
"I was elected to empower the members of the party".
But he has also claimed they are being forced out the party by supporters of Mr Corbyn - something denied by Mr Corbyn.
It also revealed how only 17% of those polled felt leader Jeremy Corbyn was performing either "well" or "very well", compared to 19% who answered "badly" and 31% who said "very badly".
"I don't know whether the press reports that Chuka has been in conversations with the Liberal Democrats and others about forming a new centrist party are true", he told BBC News.