Andrew Neil predicted that the row over Marine Le Pen "will not end well for the French political establishment". The veteran journalist issued the warning after the far-right leader was found guilty of embezzling European funds to finance her National Rally party.
She has been barred from seeking public office for five years, meaning she will not be able to run for the French presidency in 2027. She was also sentenced to four years' imprisonment, with two to be served under house arrest and two suspended.
In a post on X, Mr Neil said: "I suspect the jail sentence for Marine Le Pen plus banning her from running for president in 2027 (she is currently favourite in many polls) will not end well for the French political establishment.
"Even centrists and centre-right wondering aloud if the punishment has not been heavy-handed — and fear it will rebound to the National Rally’s advantage."
US tech billionaire Elon Musk also warned that the ban on Ms Le Pen from running for office would “backfire”.
He said on his X social media platform: "This will backfire, like the legal attacks against President Trump.
"When the radical left can’t win via democratic vote, they abuse the legal system to jail their opponents.
"This is their standard playbook throughout the world."
Ms Le Pen slammed the ruling a “political” move aimed at preventing her from running in the 2027 presidential election.
She told French broadcaster TF1: “Millions of French people are outraged. In France, the country of human rights, judges have applied the laws of an authoritarian regime.
“This is a tragic day for our democracy, with millions of French people deprived of their candidate."