Republican frontrunner Donald Trump has threatened to withhold £700m of investment in Scotland if he is banned from entering the UK.

As British MPs prepare to debate later this month whether or not the US presidential hopeful should be refused permission, Mr Trump has said any restrictions on his movement to Britain would see him withdraw millions of pounds of investment from golfing projects in Scotland.

The debate in parliament comes after the billionaire presidential candidate called for a temporary ban on Muslims entering the US. It was scheduled after more than half a million people signed a government petition.

Donald Trump plans to investment hundreds of millions of dollars in resorts in Scotland (AP)

In a statement issued on Wednesday, the Trump Organisation said its plans to invest a total of £700m in the billionaire’s two Scottish golf resorts – Trump Turnberry in south Ayrshire and the Trump International Golf Links near Aberdeen – would be suspended if any such measure was taken.

“Any action to restrict travel would force The Trump Organisation to immediately end these and all future investments we are currently contemplating in the United Kingdom,” it said.

“Westminster would create a dangerous precedent and send a terrible message to the world that the United Kingdom opposes free speech and has no interest in attracting inward investment.”

The company said banning Mr Trump from the UK would also “alienate the many millions of United States citizens who wholeheartedly support Mr Trump”.

It added: “Many people now agree with Mr Trump that there is a serious problem that must be resolved. This can only be achieved if we are willing to discuss these tough issues openly and honestly.”

Home Secretary Theresa May will make the ultimate decision about Mr Trump (PA)

Mr Trump prompted widespread condemnation last month when he suggested there should be a “total and complete” shutdown on Muslims entering the US to prevent terrorist attacks.

He spoke out after a Muslim couple, Syed Rizwan Farook and Tashfeen Malik, attacked a health facility in San Bernardino, California, that left 14 people dead and wounded more than 20.

A poll taken at the time suggested that up to a third of Americans supported Mr Trump’s proposals. More than 30 US states - the majority run by Republican governors - said they would do everything in their power to block the settlement of up to 15,000 Syrian refugees, that President Barack Obama wants to bring to the US.

In the wake of the comments, David Cameron described his comments as “divisive, unhelpful and quite simply wrong” but said the billionaire should not be banned from Britain.

However, Mr Trumps remarks sparked more than 560,000 people signed a petition calling for him to be prevented from travelling to the UK, and on Tuesday the House of Commons petitions committee said a Westminster Hall debate on the issue would be held on 18 January.

Despite that, there will be no vote at the end of the debate and it the decision on whether or not to ban Mr Trump will ultimately be decided by Theresa May, the Home Secretary.