The Labour Shadow Cabinet member was pressed to give a successful example of socialism after she pledged her party would spend £250billion if it was in Government.

A member of the Newcastle audience said: “I’d like to hear an example of a country where Corbyn and McDonnell’s economic ideas have worked.”

In a moment of embarrassment, the Shadow Foreign Secretary seemed unable to think of a successful example of a country where her party’s policies had been implemented.

Avoiding David Dimbleby’s instructions to name “one country”, the senior Labour politician appeared to try and stall for time.

As the audience laughed at her inability to answer the question Mrs Thornberry said: “I would suggest that actually, the Labour party is a social democratic party, pretty much from the centre of Europe.”

Continuing to ramble before the host interrupted her she added: “And if you look at European economic policies throughout, which are successful policies, where they invest in their infrastructure, where they invest in safety nets…”

After more than thirty seconds of thinking time and after Mr Dimbleby told the Labour frontbencher that she had failed to name a successful socialist country, the Islington South MP tried to rescue her argument naming the EU’s Germany as an example.

The audience continued to laugh at the miserable attempt to answer the question as the host exclaimed: “You should have spoken up before".

Since Jeremy Corbyn became Labour leader in 2015 he has moved the party’s policies to the hard left.

In the General Election earlier this year the socialist promised a hike on income tax.

Labour has also announced they are considering increasing council tax for eight million families, with some facing a 100 per cent rise.

They also pledged to spend billions of pounds renationalising the railways and abolishing tuition fees.

When the Conservative party came to power in 2010 they had to cut public spending across the country to reduce the UK’s deficit that had spiralled out of control under the Labour party.

In 2008 the UK borrowed more than £150billion to fund Labour’s spending.

Examples of socialist countries around the world include Venezuela who are facing a humanitarian crisis after their weak economy led to them defaulting on its debt.

In 2013, before Venezuela’s disastrous economic plan failed, Mr Corbyn hailed Venezuela for marching towards the Labour leader’s socialist ideals.

He claimed Maduro’s now-crumbling nation provided “inspiration to all of us fighting back against neoliberalism and austerity in Europe and showing us there is a better way of doing things.

He added: “It’s called socialism, it’s called social justice and it’s something that Venezuela has made a big step towards.”

Earlier this year the Chancellor Philip Hammond described the nation as “a country rich beyond imagination in natural resources but where the economic policies of Hugo Chavez, publicly supported by Jeremy Corbyn, have so tragically impoverished the country that it can longer feed its people,” adding the current state of inflation is “over 1,000 per cent” while the South American state’s growth “will fall for the fourth year in a row”.