Le Pen's hard-left rival Jean-Luc Melenchon said the evaluation was unnecessary because Le Pen was "politically responsible for her political acts".

The court order, which Le Pen also tweeted, was dated to September 11. "How far will they go?!" she wrote.

She sent out an image of the court order, which she said was "incredible", adding, "This regime is really starting to worry me". She is on trial for violating French laws regarding the distribution of messages that "incite terrorism or pornography or seriously harm human dignity". The charges stem from Le Pen's decision to post the images, including a photo of decapitated U.S. journalist James Foley, after the Paris terror attacks in November 2015. The material included a picture of US journalist James Foley's body, after the 40-year-old had been beheaded by jihadists. "I will wait to see how the magistrate intends to force me", she said.

The corresponding decision the judge made the decision in the case initiated due to the fact that in 2015, Le Pen has published three photos with the executions of people killed by terrorists so-called "Islamic state".

Italian Deputy Prime Minister Matteo Salvini also took to Twitter to express support for the French politician.

"A prosecutor has ordered psychiatric tests on Marine Le Pen".

Le Pen's National Rally is noted for its populist policies and anti-immigration sentiment. Le Pen captioned the images with the words: "Daesh is this!"

The case against Le Pen began in March, after she was stripped of her parliamentary immunity.

The other images showed a tank running over a man in an orange jumpsuit, while another jumpsuit-clad man was shown in a cage being burned alive.

If convicted, she could face up to three years in prison or a €75,000 fine. She later deleted the tweet showing Foley at the request of his family, and said she had not been aware he was in the photo.

Another National Rally lawmaker, lawyer Gilbert Collard, has also been charged for tweeting pictures of IS atrocities.

In the second round of the French presidential elections in 2017, lost to the incumbent President the Emmanuel Macron.

Last week, she repeated warnings that her party's existence was at stake if it didn't manage to win back two million euros in subsidies seized as part of an inquiry into claims it misused millions' worth of European Parliament funds.