Prior to the election, the Tories held the authority by 23 councillors to 22.
But May's party lost control of the highly prized council in the Trafford area of the northern city of Manchester - its only foothold in an important Labour-dominated economic region where the Conservatives have spent years trying to win support.
Theresa May's party appeared to have benefited from an nearly total collapse in the Ukip vote, which saw the Eurosceptic party shed councillors across the country.
Helen Elizabeth Adkins polled 1,164 votes for Labour, the Green Party's Martin Luckhurst was 1,139, the Conservative candidate, Stacey Jacqueline Calder, won 286 votes while Christopher Begg, for the Liberal Democrats, polled just 36 votes.
The unexpected surge by the Lib Dems shaved Labour's majority to just five in a night of high drama which also saw Hull's first Asian councillor elected.
Theresa May's ruling Conservatives avoided a feared rout in local elections in London, and managed gains outside the capital - according to partial results from Thursday's local elections in England.
Labour's Ashley Minto polled 1525, the Greens' Jenny Barnes 297 and James Read for the Lib Dems 266.
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Congress leader and former Chief Minister Ashok Gehlot said he was cancelling his birthday celebration on Thursday. The state government has said that the families of the dead will receive 400,000 rupees ($6,000) in compensation.
Conservative former party chairman Grant Shapps, who has been highly critical of Prime Minister Theresa May's leadership, said No 10 and Tory headquarters had "got their act together".
Two of the three new Conservative city councillors are familiar faces, with Christopher Reid and Hilton Spratt now Lincolnshire county councillors.
Leading pollster Sir John Curtice, professor of politics at the University of Strathclyde, said there was little for Labour to celebrate in the results. There was also an unforeseen double win for the Green Party in Altrincham with Dan Jerrome and Geraldine Coggins creating a historic event for the party as they have never had a seat in Trafford previously.
There are now nine Conservative councillors to go with the 24 from Labour. The seats that we have lost are very marginal seats so we expect over the years to sway this way and that.
The Tories also gained three seats.
Fareham, too, remains under Tory control with no overall change in the numbers. "This must have been very worrying for Labour so soon after last year's General Election result".
The Tories retained control of Wandsworth Council, last won by Labour in 1974, after winning more than half the seats, as well as Westminster City Council.