Labour suffered a series of major blows in its former south Wales heartlands last night, losing control of three councils in the region as well as a fourth, Flintshire, in the north of the country.

In a further setback for the party, the Conservatives took overall control of the Vale of Glamorgan from a Labour-Plaid Cymru coalition, doubling the number of Welsh Tory councils to two.

David Cameron flew into Barry, in the Vale, in an upbeat mood. Greeting councillors and supporters outside the library in King's Square, the Conservative leader quoted phrases from Gavin And Stacey, the BAFTA award winning comedy series partially set in Wales.

“What’s occurring?” Mr Cameron asked, echoing the Nessa character in the series – a tattooed, chain-smoking single mother who in one episode reveals she had an affair with John Prescott.

Using another Gavin and Stacey catchline, Mr Cameron said that his party’s win in the Vale of Glamorgan made it a “tidy” day for Wales.

"What we have seen is one sensible step after another, people looking at us seeing it’s a modernised party indeed, a party working for people in Wales and offering people choices," he told the crowd.

“We can really build from here, not build on Labour’s failings but prove to people we can make the changes they want to see."

Meanwhile, Labour councillors were left to count the cost of the party’s UK-wide unpopularity. In Torfaen, south Wales, Labour was decimated, losing 18 of its 34 seats. The long-time stronghold fell to no overall control, with independents gaining nine to become the second largest group.

In Blaenau Gwent, it was again independents who dealt the knock-out blow to Labour’s long-standing majority. Along with People’s Voice, the local party that took the Westminster and Assembly seats from Labour in recent elections, they now hold 23 seats to Labour’s 17 after the latter lost eight councillors.

Merthyr Tydfil also fell to independents, who took 19 seats, with Labour reduced to eight after losing nine seats. The party is now just two ahead of the Liberal Democrats, who went from having no representation on the council to holding six seats.

In Flintshire, north Wales, the losses were even heavier, with Labour dropping 13 seats and the council falling to no overall control.

Yet again, it was independents - already the ’second party’ across Wales after the 2004 elections - who ended up as the biggest group.

As the results began to come in last night, Rhodri Morgan, the First Minister and Welsh Labour leader, said the tide was "turning strongly" against his party, but it was "important not to panic".

"If Labour voters are disaffected they are not going to come out and we are going to lose seats," he said.

But with only nine of the 22 Welsh unitary authorities officially declared so far this morning - only one of them, Neath Port Talbort, for Labour - the picture could look even grimmer for the party by the end of today.

In Newport, the last major urban authority in the country that remained in the party’s hands after a terrible night at the last Welsh council elections in 2004, Bob Bright, the Labour leader narrowly held onto his seat.

Six seats in Newport will be fought at by-elections in June after the deaths of two councillors during this campaign, clouding the picture in terms of who will eventually control the council. But Labour’s majority will at best be slimmer after last night’s losses in what Matthew Evans, the Conservative leader in the city, called "the last socialist city in Wales."

In the Welsh capital, the Liberal Democrats, who have run a minority administration since 2004, made gains as Labour lost seats. With some wards still undeclared in the city, they appear set to retain control.

Plaid Cymru is braced for heavy losses in Gwynedd, the one council it controlled before yesterday, and fell short of the 22 seats it needed to win Ceredigion despite three gains that have made it the largest party.

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