DUBAI- Oman has designated ministers of foreign affairs and finance, and a new central bank chairman, titles formerly held by the ruling Sultan, in a broad restructuring of its administration, state TV said on Tuesday.

Sultan Haitham bin Tariq al-Said, who came to power in January after Sultan Qaboos bin Said died after half a century in power, maintains the titles of prime minister, defense minister, and head of the armed forces.

Oman previously had a minister responsible for financial affairs and a minister responsible for foreign affairs, whose briefs were overseen by the sultan.

The reforms come as Oman, a relatively small Gulf oil producer whose debt is rated "junk" by all major ratings agencies, is struggling with a widening budget deficit and an economic downturn caused by the double blow of low oil prices and the coronavirus crisis.

In a series of decrees restructuring the administration, Badr bin Hamad bin Hamoud Al Busaidi became foreign minister and Sultan bin Salem bin Saeed al-Habsi became finance minister.

Taimur bin Asaad bin Tariq al-Saeed became central bank chairman.

The decrees also dissolved and merged government bodies into new ministries, renamed entities and redefined functions.

One of the weakest economies in the hydrocarbon-reliant Gulf, Oman is burdened by high levels of debt and is more vulnerable to oil price swings than most of its wealthier neighbours.

Sultan Haitham said earlier this year the government would work to reduce public debt and restructure public institutions and companies to bolster the economy.

Fitch Ratings this week cut Oman's credit rating for the second time this year citing the continued erosion of its fiscal and external balance sheets. 

(Reporting by Nafisa El Tahir, Lisa Barrington, Dahlia Nehme and Davide Barbuscia Writing by Lisa Barrington Editing by David Holmes) ((lisa.barrington@thomsonreuters.com;))