Saudi Arabia's King Salman ordered on Wednesday a one-month salary bonus for all military and security personnel to convey his "appreciation of their efforts", the official SPA news agency announced.

The decree came after the king earlier in the day appointed a new heir and second-in-line as part of a major cabinet reshuffle, and after the most intense activity by the Saudi military in several years.

Since late March, a Saudi-led coalition has been bombing Iran-allied Houthi rebels in Yemen, and authorities said last week that security forces had gone on alert for a possible militant attack on a shopping mall or energy installation.

SPA did not say how much money would be disbursed for the bonus, but it is likely to be sizeable; the armed forces, including the national guard and paramilitary forces, are estimated by analysts to exceed 200,000 active-duty personnel.

Royal bonuses at times of political change or tension have a long history in Saudi Arabia. To mark his accession in January, King Salman ordered the payment of two months' extra salary and pensions to government employees and retirees. Lavish social welfare spending was announced during the Arab Spring uprisings elsewhere in the region in 2011.  - Reuters