Ukip MEP Nigel Farage told Herman Van Rompuy, the president of the EU, he had "all the charisma of a damp rag and the appearance of a low-grade bank clerk" in the European parliament yesterday.

Farage, the former leader of the UK Independence party, also dismissed Van Rompuy's homeland, Belgium, as a "non-country".

As well as attacking Van Rompuy's appearance, personality and home nation, Farage also criticised the president's pay packet and accused him of plotting the overthrow of the nation state.

Van Rompuy, who had just made his first speech to MEPs since being appointed by EU leaders to the newly-created top job, sat in amazement and obvious discomfort as the tirade went on. Other MEPs in the less-than-full chamber gasped as Farage spoke.

Afterwards the Socialist leader in the parliament, Germany's Martin Schulz, condemned Farage for "trampling on the dignity of the house".

And Van Rompuy responded that he held Farage's remarks "in contempt", and refused to say more.

Farage – who is challenging the Speaker of the Commons, John Bercow, in Buckingham at the general election – declared: "We were told that when we had a president, we'd see a giant global political figure, a man who would be the political leader for 500 million people, the man that would represent all of us all of us on the world stage, the man whose job was so important that of course you're paid more than President [Barack] Obama."

He continued: "Well, I'm afraid what we got was you ... I don't want to be rude but, really, you have the charisma of a damp rag and the appearance of a low-grade bank clerk and the question I want to ask is: 'Who are you? I'd never heard of you. Nobody in Europe had ever heard of you.'"

Farage went on: "I can speak on behalf of the majority of British people in saying that we don't know you, we don't want you, and the sooner you are put out to grass, the better."

The former Ukip leader told Van Rompuy: "I have no doubt that your intention is to be the quiet assassin of European democracy and of European nation states."

That, added Farage, was probably because Van Rompuy came from "pretty much a non-country" so had no interest in the nation state.

Van Rompuy, 62, was the surprise compromise choice as the new president of the council – a role created by the Lisbon treaty and one which some thought should and would go to Tony Blair as an internationally-recognised new face for the EU.

Van Rompuy, the former Belgian prime minister, was credited with turning his country's fortunes around last year.

He made clear he would not be a "globe-trotting" leader of the EU, considering himself more a "chairman" of the EU's council of national governments.

The centre-right politician quietly enjoys his nickname as the "grey mouse" and is known for writing haiku poetry.

Given a final say in the form of a right of reply after Farage and other – friendlier – MEPs had commented on his speech, Van Rompuy remarked: "There was one contribution that I can only hold in contempt, but I'm not going to comment further."