The UAE, a federation of seven emirates with a mostly expatriate population, is a key member of a Saudi-led military coalition that intervened in Yemen in 2015 against the Iran-aligned Houthi movement to restore the internationally recognised Yemeni government in exile.
"The general command of the armed forces ... announced the extension of the legal period for national service ... to 16 instead of 12 months," WAM said late on Saturday.
The UAE introduced mandatory military service in 2014 for Emirati men. It kept participation for women, who can serve only for nine months, optional and requiring approval of their legal guardians.
Men who hold a high school diploma or its equivalent will serve 16 months instead of 12, while those who do not have a high school qualification continue to serve for two years.