Mrs Long-Bailey told BBC Radio 5 Live that Sir Keir's motion, hammered out after a late-night meeting, respected the 2016 referendum result.
By saying he will vote against Chequers, he has thrown down the gauntlet to May, who has promised to press on with her plan to leave the European Union, named after her country residence where an agreement was hashed out with her ministers in July. Longstanding EU opponents like veteran MP Dennis Skinner were unimpressed.
Labour would aim to double the UK's onshore fleet by 2030, up from a current 12.2GW, along with an increase in offshore capacity to 52GW, up from about 8GW now, party officials told its annual conference.
May's position, already precarious, was further weakened last week when the European Union rebuffed her Brexit proposal, known as "Chequers", which is also unpopular in her Conservative Party.
She told ITV's Peston programme: "I've talked to a number of colleagues and conservatively there are about 40 of us who would not support a Canada-style deal".
Mr. Corbyn spoke for more than an hour, setting out his vision for a "fairer society under Labour" to enthusiastic support in the hall.
The U.S. Federal Reserve is expected to raise interest rates for the third time this year later on Wednesday, and investors will be looking for clues as to whether the central bank will ramp up the pace of policy tightening following signs of an acceleration in U.S. economic growth.
With seven months until Britain officially leaves the bloc, negotiations faltering, chances are rising of an acrimonious divorce - and the one thing that pro- and anti-EU forces have in common is that they are both unhappy.
"All he offers are failed ideas that didn't work in the past and would leave working families paying the price with higher taxes, more debt and more waste - just like last time", he said.
"That must include campaigning for a public vote", he said.
"The risk is growing that the only option to avoid a no-deal scenario will be to have a rather hollow political declaration on the future EU-UK relationship, which will accompany the withdrawal agreement".
The U.K. government says it remains confident of reaching a deal, but is preparing for a "no deal" scenario.
The prime minister will attempt to reassure business leaders on Wednesday that the United Kingdom services industry and London's role as a financial centre will stay "the envy of the world" after Brexit.
"The prime minister made clear we're going to keep our calm, hold our nerve and press the European Union on some of the criticisms that they've made, but also to be clear that there are no credible alternatives that the European Union has come up with", Raab told the after the meeting.