An employer may terminate an employment contract because an employee has breached their obligations or their capacity for work has decreased, provided that a warning has preceded the termination.
The law does not prescribe a mandatory form or content for a warning. A warning may be given orally, in a form that can be reproduced in writing (for example, by email), or in writing. The employer must subsequently be able to prove that the warning was given.
If the employer wishes to terminate the employment contract extraordinarily following a repeated breach, the warning should expressly refer to the possibility of terminating the employment contract.
The employee should receive a description of the circumstances and facts explaining what happened, together with a warning that the employer may terminate the employment contract extraordinarily if the conduct is repeated or continues. Receipt of a written warning could be confirmed by the employee’s signature and the date of receipt.
A prior warning is not required as a condition for termination if, because of the particularly serious nature of the breach or for another reason, the employee cannot reasonably expect the employer to give a warning in accordance with the principle of good faith.

