Saudi Araba's ambassador to the UK has attacked Labour leader Jeremy Corbyn for suggesting the kingdom supports Islamic State (IS, formerly ISIS/ISIL).

Prince Mohammed bin Nawaf bin Abdulaziz al Saud described comments made by Corbyn and former Liberal Democrat leader Paddy Ashdown as "distortion" and "an insult" to the Saudi Arabian government.

The Labour leader said on Tuesday there were several "very big questions" around the rise of IS which remained unanswered, such as who is providing financial aid to the group.

Corbyn suggested Saudi Arabia may be involved in funding IS, a theory shared by many journalists and Middle East analysts.

Writing in the Times, Prince Mohammed rebutted allegations Saudi Arabia is supporting jihadists in Syria.

"As the scourge of terrorism continues to spread, the blame game has begun. Saudi Arabia finds itself once again targeted by politicians such as Jeremy Corbyn and Lord Ashdown, who wrongly suggest that in some way we support radical extremism," he said.

"I prefer to believe this is misunderstanding, not malice. The contrary is an insult to our government, our people and our faith."

The ambassador said his country "knows the reality of terrorism intimately" and has been fighting it "for decades."

On the question of funding, he insisted Saudi Arabia had "stringent laws" to stop financial support from private individuals or societies reaching terrorists.

The kingdom's cooperation with international partners in fighting terrorism had made the world a safer place, he said.

"However, the common mischaracterization of Saudi Arabia's role in the war on terror, perhaps deliberately and for political point-scoring, stands to impede cooperation going forward."

Speaking in the House of Commons on Tuesday, Corbyn said it is important to learn who is supporting IS before extending airstrikes against the group from Iraq into Syria.

"Who is funding ISIS? Who is arming ISIS? Who is providing safe havens for ISIS? You have to ask questions about the arms that everyone has sold in the region, the role of Saudi Arabia in this. I think there are some very big questions."

Ashdown made similar allegations against Saudi Arabia when he called the close ties between the British Conservative Party and the Gulf state "worrying."

"The failure to put pressure on the Gulf states – and especially Saudi and Qatar – first of all to stop funding the Salafists and the Wahhabists, secondly to play a large part in this campaign, and other actions where the Government has refused to have a proper inquiry into the funding of jihadism in Britain, leads me to worry about the closeness between the Conservative Party and rich Arab Gulf individuals."

Saudi Arabia: Fawning Cameron starts charm offensive as relations falter https://t.co/N9LRZxTVnkpic.twitter.com/jPj7LTzCpL — RT UK (@RTUKnews) October 30, 2015

The ambassador's comments follow a threat of legal action by a Saudi justice ministry official over a tweet which called the country's capital punishment regime "ISIS like."

The tweet, the source of which has not been identified, was in response to a satirical cartoon which compared Saudi Arabia to IS.

Illustrator Peter Brookes published the cartoon in the Times on Saturday.

My cartoon Saturday @TheTimes. Isis is a barbaric death cult...what about some of our allies? #syriaairstrikespic.twitter.com/QkA4QLp9kq — Peter Brookes (@BrookesTimes) November 28, 2015

"The justice ministry will sue the person who described … the sentencing of a man to death for apostasy as being 'ISIS-like," the Saudi official said.