Americans should vote for Donald Trump as president next month or risk being dragged into an apocalyptic nuclear war, a close ally of Russian leader Vladimir Putin has threatened.

Vladimir Zhirinovsky, a flamboyant lawmaker known for his fiery rhetoric, said the Republican candidate was the only person able to calm the growing tension between Moscow and Washington.

By contrast, Mr Zhirinovsky said if Democratic rival Hillary Clinton becomes president it could spark World War Three.

Americans should vote for Donald Trump as president, a close ally of Russian leader Vladimir Putin has threatened

Many Russians regard Mr Zhirinovsky as a clownish figure who makes outspoken statements to grab attention – but he is also viewed as a faithful servant of the Kremlin who is sometimes used to float radical opinions to test public reaction.

'Relations between Russia and the United States can't get any worse. The only way they can get worse is if a war starts,' said Mr Zhirinovsky. 'Americans voting for a president must realise they are voting for peace on planet Earth if they vote for Trump. But if they vote for Hillary, it's war. There will be Hiroshimas and Nagasakis everywhere.

'Victory for Trump would be a gift to humanity. But if Hillary Clinton wins she will be the last US president ever.'

Mrs Clinton has previously accused Mr Trump of being too cosy with Putin and questioned his business interests in Russia. But in comments that delighted Moscow, Trump has questioned the value of Nato, spoken about Russia's annexation of Ukraine's Crimea in 2014 and suggested that the United States under his leadership would adopt a more isolationist foreign policy.

By contrast, Mr Zhirinovsky said if Democratic rival Hillary Clinton becomes president it could spark World War Three

'He [Trump] won't care about Syria, Libya and Iraq, and why on earth should America interfere in these countries? Trump will have a brilliant chance to make relations more peaceful. He's the only one who can do this,' said Mr Zhirinovsky, adding that Mr Trump could even win a Nobel peace prize.

However, Mr Zhirinovsky described Mrs Clinton as 'an evil mother-in-law' and said her record as secretary of state showed she was unfit to lead her country.

If they vote for Hillary, it's war

'She craves power. Her view is that Hillary is the most important person on the planet, that America is an exceptional country,' said Zhirinovsky. 'That's dangerous. She could start a nuclear war.'

In typically chauvinistic remarks, Mr Zhirinovsky said Mrs Clinton's gender should also bar her from the presidency. 'Americans should choose Trump because men have been leading for millions of years. You can't take the risk of having one of the most powerful countries led by a woman,' he said.

Donald Trump's civil war with the Republican Party escalated as insiders claimed his financial backers were starting to ask for their money back. He has been plunging in the polls since an 11-year-old video revealed him boasting about groping women.