Chuka Umunna has accused Ukip of offering a "road to decline" and ultimately a "dead-end" in its stance towards the European Union.
The shadow business secretary, who has been one of the Labour frontbench's most outspoken critics of the eurosceptic party, made his latest attack in a speech to the Japanese Chambers of Commerce in London on Thursday night.
Umunna told the assembled businesspeople that Labour would offer an "open, outward looking approach to the world," restating his party's commitment to the European Union as he said: "Britain’s interests remain within the EU."
“We can see all around us how rapidly the world is changing – driven by rising international competition from emerging economies and technological developments transforming the way we live and learn," he said.
"Some have responded to these changes by looking backwards. They argue life was better in times past when Britain still had an Empire. They want to press the pause button on change, pull up the drawbridge to new ideas and people from abroad, and leave the international market place. But this is the road to decline. It is a dead-end. We cannot stop competition or technological advance."
Umunna has previously clashed with Ukip, after last May accusing them of "maliciously" distorting the immigration debate. The Labour frontbencher has spoken of being subject to "racist and vociferous" abuse from Ukip supporters, accusing the party of stoking up "fear, division and loathing in our community".
This comes as senior politicians accused Ukip leader Nigel Farage of exploiting Wednesday's terrorist attack in Paris for his own political gain, after he suggested multiculturalism was to blame.
Deputy Prime Minister Nick Clegg told LBC radio this morning he was "dismayed" at the Ukip leader's response to the "horrific, cold hearted, cowardly attack" on the offices of French satirical magazine Charlie Hebdo in which 12 people were killed.
Umunna also lambasted Prime Minister David Cameron for his "hostile approach" to Britain's European partners, warning: "It has already compromised our influence abroad."
He added: “Instead of the positive political leadership that is needed to reform and modernise the EU our influence is declining. Labour will reverse this and put the UK back in the driving seat.”
Urging businesses to make their voices heard in the debate on Britain's membership of the European Union, he went on: "When Nissan spoke out about the implications for their business if Britain left the EU, they were right to do so. Quite obviously, whether we are in or out of Europe we want firms like Nissan to stay in Britain. I believe your success here shows there are many good reasons why you should do so."
Brexiters
Nigel Farage(01 of09)
Open Image ModalThe Ukip leader and MEP is the most famous 'outer'. After his party took over a 100 council seats in May's local election's Nigel Farage is hoping to win the 2014 European elections and then gain MPs in Westminster in 2015. He has confirmed he will seek a parliamentary seat himself. (credit:PA)
Lord Lawson(02 of09)
Open Image ModalMargaret Thatcher's former chancellor and a true 'Tory grandee' revealed in The Times that if and when there is a referendum "I shall be voting out". He also stuck the boot into the David Cameron by saying the prime minister's attempts to renegotiate the terms of the UK's relationship with the EU would be "inconsequential". (credit:PA)
Backbench Brexiters(03 of09)
Open Image ModalThere are quite a few Conservative MPs who would like to wave goodbye to Brussels. Ken Clarke has said the figure is as low as 30 despite the strong eurosceptic feeling on the backbenches. However the exact number is not clear. Mid-Bedforshire MP Nadine Dorries, who remains suspended from the Conservative Party, is currently talk tof the eurosceptic town amid rumours she may defect to Ukip. Other backbench Brexiters include Bill Cash, Douglas Carswell, Peter Bone and Philip Davies and former defence minister Sir Gerald Howarth. (credit:PA)
Labour's 'Let's Leave' Lot(04 of09)
Open Image ModalMost of the anti-EU focus is on the Tory benches. But there are more than a handful of Labour MPs would would like to quit Brussels as well. Eurosceptics include Frank Field, Kate Hoey, Austin Mitchell, and Gisela Stuart.Stuart has argued the status quo is "not sustainable" and Britain should leave. (credit:PA)
Media Moguls(05 of09)
Open Image ModalRupert Murdoch has warned that the EU will "sink" the UK. The News International and boss caused a stir when he met Nigel Farage for dinner in London recently and said the Ukip leader was "reflecting opinion" with his anti-EU views.In November 2010 Richard Desmond’s Daily Express became the first UK newspaper actively to call for Britain to leave the EU, launching a ‘Get Britain Out’ campaign (credit:PA)
I'm A Celeb, Get Us Out Of Here(06 of09)
Open Image ModalOf course no campaign is complete without a bit of star power. The pro-EU camp have Eddie Izzard, who do the Brexiters have?Joan Collins, a 'patron' of Ukip, wants the UK to leave. "The EU, controlled from Brussels, cares only about itself," she said in March. (credit:PA)
The Business Types(07 of09)
Open Image ModalMost business leaders do indeed seem content with what Lawson called the "warm embrace of the European single market", but there are a few dissenters. Private equity guys Jon Moulton and Edmund Truell are two and Next boss and Tory peer Simon Wolfson has said: "Britain should stay in Europe, but only on the right terms". (credit:PA)
The Commentariat(08 of09)
Open Image ModalThere are a number of loud voices whinnying on the sidelines to say "neigh" to the EU notably Melanie Phillips, Richard Littlejohn, Tom Utley, Simon Heffer.Basically the Daily Mail stable. (credit:PA)
Edging Towards Exit(09 of09)
Open Image ModalSeveral high-profile politicians appear to be on the verge of calling for the UK to exit the EU - but just are not there yet.Former defence secretary Liam Fox - pictured here with a big gun - has said "life outside the EU holds no terror" should David Cameron's hopes of negotiating a new treaty fail.Education secretary Michael Gove is said to have told friends the UK has "nothing to be scared of" by leaving Europe.And many other eurosceptic cabinet ministers, including Iain Duncan Smith and Owen Paterson are likely to share that view. (credit:PA)
See more on the 2015 General Election here