Donald Trump has been forced to backtrack over claims that he saw a video of a plane flying $400 million (£307m) in cash to free hostages in Iran.

As fellow Republicans criticised president Barack Obama for shipping cash to Iran, Mr Trump was quick to jump on the bandwagon - but he went one step further.

At a rally in Florida this week, he claimed that he had seen a video of people in Iran unloading money from the plane.

His assertions came despite his campaign team's denials that the tape existed. They said that the video, aired on Fox News, actually showed American hostages landing at Geneva.

A day later in Maine he said: "A tape was made, you saw that? With the airplane coming in … and the money coming off, I guess, right?"

"You know why the tape was given to us? Because they want to embarrass our country."

Trump boasts about watching 'top secret' Iran video

Now Mr Trump has backtracked on his claim by posting a message on twitter.

"The plane I saw on television was the hostage plane in Geneva, Switzerland, not the plane carrying $400 million in cash going to Iran!" he said.

The Obama administration has denied the money as paid as a ransom, which critics say would only encourage adversories to take US citizens hostage in return for money.

The government said the cash was part of resolving an old dispute. Iran has long claimed that the US owed them $1.7 billion for failing to carry out a 1979 arms deal.

It was also the right time, Mr Obama said, after he had signed a deal in January to halt Iran’s nuclear power plans.

Speaking about the release of prisoners on 17 January this year, he said: "With the nuclear deal done, prisoners released, the time was right to resolve this dispute as well."

The money was flown on an unmarked plane in euros and other currencies acquired from the central banks of the Netherlands and Switzerland, since making a transaction with Iran in US dollars is illegal under US law.