RIYADH - Saudi Arabia's new King Salman has tightened his hold on power, firing two sons of his predecessor and replacing the heads of intelligence and other key agencies in a sweeping shakeup.

The appointments, which analysts said supported signs the kingdom will chart a steady course on foreign and oil policy, came a week after Salman, 79, took the throne following the death of King Abdullah.

Top officials from the Ports Authority, the National Anti-Corruption Commission and the conservative Islamic kingdom's religious police were among those let go late Thursday.

But the oil and foreign ministers retained their key posts.

The changes confirmed speculation that Abdullah's death "would see a reversal in his immediate family's fortunes," said Jon Marks, a Middle East expert at London-based think-tank Chatham House.

"We have a situation of change in a highly personalised hierarchy, but not -- at least not immediately -- of significant policy change."

Salman also reached out directly to his subjects. One of his more than 30 decrees ordered "two months' basic salary to all Saudi government civil and military employees," the Saudi Press Agency (SPA) said.

Students and pensioners got similar bonuses.

"Dear people: You deserve more and whatever I do will not be able to give you what you deserve," the king said later on his official Twitter account. (AFP)