THE president of Mexico has joined Scotland's row with Westminster over Scottish independence, saying the UK must honour the principles of "participant democracy".

Andres Manuel Lopez Obrador said it was important to settle polarising and complicated questions through "direct democratic methods".

He went on to say that the principle of "participant democracy" was set with the Brexit referendum and that it should be offered again to the people of Scotland.

He told the Daily Express: "It is important to gather the opinion of the people and give a voice to the people.

"When an issue is polarised and complicated the best way to gather the answer is to give the choice to the people.

"How can you say you know what the people want and that you are ruling on their behalf without asking them what they want?

"It is important politically, economically, and socially, culturally to have citizens partake in participant democracy and best to collect the opinion of the people."

READ MORE: Nicola Sturgeon tells Boris Johnson indyref2 is 'a matter of when not if'

Lopez Obrador compared indyref2 a recent referendum that he granted in Mexico. He said he let the Mexican people have the final say over a controversial Mexican infrastructure project because a nation "that is considered a democracy" should have decisions "selected directly by the people".

In 2018 plans to scrap a part-built multibillion-dollar airport near the capital, Mexico City, were abandoned after the result of a public referendum.

However, the move put Lopez Obrador's administration on a collision course with investors.

The referendum on whether to build the airport in Texcoco, outside Mexico City, was used as a way to sever links to the vested interests from the past Mexican administration.

Nicola Sturgeon told Boris Johnson another referednum on independence is "a matter of when not if" in the wake of the SNP’s historic election win at the Holyrood election.

Downing Street said Johnson finished his call with the SNP leader by "emphasising the importance of focusing on Covid recovery at this time". The report by Number 10 made no mention of any constitutional issues.

The SNP won the election with 64 MSPs, and Holyrood will have a pro-independence majority with eight Scottish Greens also elected.

In her victory speech, Sturgeon said Scotland had voted for a second independence referendum and declared it “the will of the people”.