Dozens of French opposition MPs have launched an attempt to impeach President François Hollande, reports BBC News.
The conservative deputies allege that the socialist president disclosed classified information to journalists, published in a book recently. The MPs have sent the motion to the government.
Pierre Lellouche, who began the process, said Mr Hollande had "seriously violated defence secrecy".
However, the impeachment attempt faces a number of difficult hurdles.
The motion was signed by 79 deputies from The Republicans party. But 152 support the measure, the party told the AFP news agency.
Article 68 of the French constitution - which Mr Lellouche and his supporters are attempting to trigger - says that the president may not be removed from office except for "a breach of his duties patently incompatible with his continuing in office".
Impeachment can only be achieved by a two-thirds majority of both the Assembly and Senate by secret ballot, in a special sitting where parliament acts as the high court.
Mr Hollande's Socialist Party controls 51% of the National Assembly seats, and 37% of the Senate.
The proposal must also be approved by France's committee on laws before it reaches parliament.
The controversial book at the centre of the accusations, A President Should Not Say That, is a record of dozens of private conversations with two journalists, collected over several years.
It included Mr Hollande's comments on Syrian air strikes, and the admission that he personally ordered the assassination of four enemies of the state, among several other controversial statements.
The publication of the book was widely seen as "political suicide" ahead of France's 2017 presidential election, and saw Mr Hollande's approval rating sink to a new low.
In a poll, 78% of those surveyed said it was a mistake for Mr Hollande to give the interviews, and 86% said they did not want him to run for a second term.
The controversy comes at a crucial time for Mr Hollande, ahead of April's presidential elections.
Read more of this report from BBC News.
See also:
Furious socialists turn backs on 'verbally incontinent' Hollande
New book reveals François Hollande's disturbing approach to corruption scams