Donald Trump has issued an executive order allowing fresh sanctions on people or countries who attempt to interfere in US elections.

Concerns about potential foreign meddling have intensified in the US ahead of the mid-term congressional elections in November.

It also comes amid the continuing investigation by special counsel Robert Mueller into alleged Russian interference ahead of the 2016 presidential election.

In the new executive order, President Trump says: "Although there has been no evidence of a foreign power altering the outcome or vote tabulation in any United States election, foreign powers have historically sought to exploit America’s free and open political system.

"In recent years, the proliferation of digital devices and internet-based communications has created significant vulnerabilities and magnified the scope and intensity of the threat of foreign interference."

If anybody or country is found to have meddled under the next order, potential sanctions include heavy restrictions on access to US banks or property.

The executive order has already drawn criticism, with Democratic Senate minority leader Chuck Schumer saying Donald Trump "giving himself the option of levying tough sanctions is hardly reassuring".

The new executive order certainly does not absolve the Senate from passing much-needed legislation and funding to beef up our election security and prevent future attacks on our democracy from foreign adversaries.

— Chuck Schumer (@SenSchumer) September 12, 2018

Republican Senator Marco Rubio, meanwhile, said the White House did what they could do with an executive order, but added the Trump administration is "limited from going further without legislation" from Congress.

While Donald Trump has suggested Russia was likely to have interfered in the 2016 election, he has repeatedly insisted there was no collusion between his campaign and Russia.