What is the ruling on an employee receiving compensation for travel expenses that he did not incur, or signing off on fictitious travel expenses to enable a colleague to obtain compensation after exhausting his allotted travel period?

The aforementioned transaction is a trick to enable the employee to take company money he does not deserve. It is forbidden because of Allah Almighty’s saying: "O you who have believed, fulfill [all] contracts," and the Hadith (definition): "Muslims are bound by their conditions." Whoever has taken anything in this manner must return it to his employer or spend it on charitable causes and for the benefit of Muslims.