Mauritania's new President Sidi Ould Sheikh Abdallahi and his cabinet have decided to take a 25% pay cut.
It is not clear how much President Abdallahi earns
Local journalist Hamdi Ould Nohamed el-Hacen told the BBC it has come into effect immediately.
It was prompted by "reduced petroleum revenues", AFP news agency quotes a cabinet statement as saying.
Mr Abdallahi won run-off elections in March to become Mauritania's first democratically elected leader since independence from France in 1960.
The country was under the autocratic rule of Maaouiya Ould Taya for 25 years until a military coup in 2005
One of the world's poorest countries, Mauritania has pinned hopes for future prosperity on the exploitation of its offshore reserves of oil and gas.
Correspondents says oil production in Mauritania is currently around 18,000 barrels a day, compared to the originally anticipated 75,000 bpd.
According to AFP news agency, until Thursday ministers earned a monthly salary of about $3,500, compared to an average civil servants' pay packet of $260.
The president's salary was not reported.
The austerity measure follows last week's government announcement of a $112m budget deficit, the agency reports.