Former UKIP leader Nigel Farage has denied being invited by Donald Trump to attend the Republican National Convention in Cleveland, Ohio, after a surprise visit to the RNC as an “observer.”

Farage, who played a key role in the campaign for Britain to vote ‘Leave’ in the recent referendum on EU membership, said he was attending the event to hear the presumptive Republican nominee’s speech.

The right-wing politician arrived in the US on Tuesday, and is expected to speak with Euroskeptic Republican politicians over breakfast on Wednesday morning.

Farage said he did not plan to endorse Trump or any other candidate in the US election after having criticized US President Barack Obama for his intervention into the Brexit debate earlier this year.

However in an interview with CNN’s Richard Quest shortly after the EU referendum, he said he thought Trump would be “better” than Obama.

The prominent Euroskeptic told USA Today that he felt the US could learn lessons from the EU referendum, but did not go into details.

“Having criticized President Obama for getting involved in British politics, I am not about to endorse anybody,” Farage said.

“But I do know a lot of people in the Republican Party, and I'll be interested to hear what Donald Trump has to say in his big speech.”

‘Voting is not enough’: Photoshoot with 100 naked women to greet Trump & RNC in Ohio https://t.co/MqxXe6lauLpic.twitter.com/DuhdiCfQic — RT (@RT_com) May 13, 2016

At the time of the referendum, Farage effectively endorsed the Republican presumptive nominee for president.

“A Trump administration pledges to strengthen ties with a free and independent Britain, deepening our bonds in commerce, culture and mutual defense.

“The whole world is more peaceful and stable when our two countries – and our two peoples – are united together, as they will be under a Trump administration.”

The former UKIP leader has expressed revulsion at the thought of presumptive Democratic nominee Hillary Clinton winning the presidency.

“There is nothing on Earth that could persuade me ever to vote for Hillary Clinton,” he previously said.

The RNC, which began on Monday, is taking place amid intense levels of security, as thousands of police officers from around the country have descended on the Mid-Western city.

Some 500 Cleveland police officers will be joined by 2,000 cops from around the US to police planned protests outside the ‘hard perimeter’ of the convention area.