Tourism Minister Edward Zammit Lewis has slammed a comment by Joe Grima, Malta’s special envoy to the World Tourism Organisation that London's new democratically-elected Muslim mayor was elected by "cockroaches".

DrZammit Lewis said the comment was inappropriate and unacceptable.

Mr Grima, himself a former tourism minister and no stranger to controversy with his anti-migrant rants, has now taken umbrage at the fact that London has elected Sadiq Khan, a Muslim, as its mayor. 

“The writing is on the wall. The cockroaches have invaded dear old London. Londoners thought they were buttering their bread by voting in an Islamic Mayor but with the butter they allowed in the cockroaches,” Mr Grima wrote on Facebook.

Mr Grima tagged his comment to a story uploaded by the pro-Israeli website supportisraelnow.com. The Labour mayor beat Tory Zac Goldsmith ending eight years of Conservative control, with the largest personal mandate of any politician in UK history.

Last year, Mr Grima stirred more controversy after he attacked President Marie-Louise Coleiro Preca for urging migrant integration. He has also described human rights NGO Aditus Foundation as “cultural rapists”.

In August 2012, he resigned as show host on the Labour Party’s TV station after he launched an attack on a priest who had written a critical obituary in The Catholic Herald of former leader Dom Mintoff.