he cartoon pictures British Prime Minister, David Cameron, kicking out of his way emigrants, wrapped in Bulgarian and Romanian national colors, to make way to a troll-like creature with the inscription UKIP (Independence Party).
UK Business Secretary Vince Cable has accused the Conservatives of being "in a bit of a panic because of UKIP" over fears of an influx of Bulgarian and Romanian migrants.
When asked by the BBC if there was a crisis in the coalition over the issue, Cable, a Liberal Democrat minister, said there was "quite a lot of tension".
UK Independence Party campaigns for tighter border controls and Britain's exit from the EU.
Vince Cable echoed earlier comments by his party leader Nick Clegg, arguing that there should not be further restrictions on freedom of movement within the EU.
Earlier, Bulgarian President Rosen Plevneliev warned that David Cameron's plans to toughen rules on immigration could harm the UK's image as a "great global power that pioneered integration".
Downing Street said that while free movement was a principle of the EU it could not be a completely unqualified one.
UKIP, which has called for withdrawal from the European Union and greater restrictions on immigration, has seen improved poll ratings this year.