Both parties appealed. UNAT held that UNDT erred by finding a valid contract of employment between Ms Al Hallaj and ESCWA since no letter of appointment was issued, only an offer of employment. UNAT held that a quasi-contract was formed, considering that Ms Al Hallaj had unconditionally accepted and had fully fulfilled all the conditions specified in the offer of employment. UNAT agreed with UNDT that the ESCWA Administration committed two major errors, in breach of its quasi-contractual obligations. UNAT held that the ESCWA Administration failed in its due diligence to specify clearly and...