The Anti-Defamation League (ADL) has welcomed an apology by US rapper Macklemore over a stage costume he wore which critics claimed was anti-Semitic. Macklemore, a.k.a Ben Haggerty, became the subject of heavy scrutiny over the weekend, after donning a fake beard and prosthetic nose for a Friday night show at Seattle's EMP Museum. Comedian Seth Rogen took to Twitter to denounce the costume, including a beard and a large hooked nose, worn by the musician at a concert last week. "First you trick people into thinking you're a rapper, now you trick them into thinking you're Jewish?" said Rogen, who is Jewish. Josh King, under the Twitter handle @chompsk1, wrote: "For those who don't know, @macklemore performed Thrift Shop dressed as a racist Jewish stereotype. idiot." Macklemore, who won four Grammys at this year's Grammy awards, issued a statement to say that the costume was not intended to represent any particular cultural stereotype. Talking about Friday's costume stunt in Seattle, he said: "I thought it would be fun to dress up in a disguise and go incognito to the event ... I picked up a bunch of fake mustaches and beards and grabbed a left over wig from our recent trip to Japan. "As it turns out the fake noses they sell at the costume store are usually big (my nose didn't fit most of them) ... I personally thought I looked very ambiguous in terms of any 'type' of person. But Rogen disagreed, tweeting: "If I told someone to put together an anti Semitic Jew costume, they'd have that exact shopping list." Macklemore later published a full apology on his website, insisting: "My intention was to dress up and surprise the people at the show with a random costume ... it was surprising and disappointing that the images of a disguise were sensationalized (as) anti-Semetic (sic)." "I'm saddened that this story, or any of my choices, would lead to any form of negativity ... I truly apologize to anybody that I may have offended," he added, saying he was already in touch with the ADL, which combats anti-Semitism, and who he praised for " the great work they do". In welcoming the apology , ADL national director Abraham H. Foxman said the entire incident had been blown out of proportion. "We know that Macklemore is someone who has used his platform in the past to stand up and speak out against intolerance and bigotry," said Foxman. "With that in mind we believe that this matter is little more than 'a tempest in a teapot' over an unfortunate choice of wardrobe."