The Chancellor was careful not to criticise people who backed the Eurosceptic party in Thursday’s polls, insisting he had “respect” both for them and Ukip leader Nigel Farage, despite him being forced to deny claims of racism over remarks about immigrants.
But dismissing calls for a Tory electoral pact with Ukip, he said the public would be confronted with a clear choice between the two main parties at the 2015 general election and that voting for the minority party could allow Labour to take power.
He spoke out as Labour sought to defend its campaign after results which suggested leader Ed Miliband was not on course to secure a Commons majority despite notching up some notable successes.
Ukip gained more than 120 seats on English councils, eating into the representation of all three main parties and making significant inroads in areas such as Essex seen as pivotal to next year’s general election result.
Mr Farage hailed the results as proof that his Eurosceptics were “serious players”, with their sights now firmly set on getting MPs elected - and continued to predict that the party would win European elections when the results are declared tomorrow.
But the scale of the “earthquake” predicted by Mr Farage was thrown into question by projections of national vote share which suggested that Ukip support had dropped since last year’s general elections from 23% to 17%.
That analysis, by the BBC, also heightened concerns within the Labour Party over its prospects of seizing power at Westminster in 2015 as Mr Miliband came under fire for a disappointing performance.
It put Labour on 31%, only two points ahead of the Conservatives and off course for outright general election victory.
Mr Miliband defended the campaign, which saw the party gain 330 seats, perform strongly in London and notch up a series of significant victories in several target locations.
But it did not secure key councils such as Swindon, was prevented from taking charge in its number two parliamentary target seat, Thurrock, by the Ukip advance, and saw nerves were heightened by strong progress for Mr Farage in traditional Labour heartlands including Rotherham.
Shadow Chancellor Ed Balls said the results were “not good enough yet” and the party had to make arguments about controlling immigration and European reform “more loudly”.
Backbenchers rounded on “pointy heads” in London for failing to confront the threat from Ukip more directly and an “unforgivably unprofessional” campaign.