Ukip has attracted criticism over its new calypso theme tune sung in a fake Caribbean accent, with lyrics about “open borders” and “illegal immigrants in every town”.

The song was performed by former Radio 1 DJ Mike Read and endorsed by Nigel Farage, who encouraged supporters to help it reach No 1 in the UK charts.

Within hours of being launched, the video was climbing the iTunes charts, at the same time as being mocked on Twitter by figures such as comedian David Baddiel and Labour’s Lord Prescott.

However, David Lammy, Labour MP for Tottenham and a former minister, did not find the song funny, saying if “we needed any more evidence of the Ukip leadership being tone deaf elitists then look no further”.

“Their ruthless pursuit of power, using references to bongo bongo land one day and cod Caribbean accents the next, will be found out for what it is: a nasty creed of politics based on fear-mongering and resentment,” he said. “Ukip’s claim that they are not a racist party gets more and more incredible with every scandal.”

Read defended his song after some objected to his appropriation of calypso music to promote an anti-immigration argument.

Speaking to BBC Radio Berkshire, he said: “If anyone has taken it the wrong way, many apologies. But it was never meant to be remotely racist … It’s an old-fashioned political satire … you can’t sing a calypso with a Surrey accent.”

The song’s second line addresses the issue of immigration, saying: “Leaders committed a cardinal sin, open the borders let them all come in; illegal immigrants in every town, stand up and be counted Blair and Brown.

In May Ukip held a “carnival of colour” in Croydon, which descended into farce as members of a steel band said they would not have accepted the gig if they had known it would be for Farage’s party.

Farage has repeatedly said Ukip is a patriotic, non-racist party that welcomes everyone. However, its position has been undermined by controversial comments made by some of its candidates, such as one who was expelled for saying comedian Lenny Henry should move to a “black country”.

Just before the local elections, Farage held an event in central London highlighting many of Ukip’s ethnic minority backers. He told the gathering that a “handful” of its thousands of candidates had made “stupid or offensive” comments, but that this in no way represented the views of the party.

It is not the first time Read has performed a political song. He rapped for 10 minutes during a dinner at a Conservative conference and expressed a desire to stand as the party’s candidate for London mayor in 2006.

He was also at the centre of a controversy in 1984 when he refused to play Relax by Frankie Goes to Hollywood on the BBC, because of its sexually suggestive lyrics.