The central African nation has experienced economic hardship since the fall in oil prices in 2014
The letter was presented by him after the country’s President Denis Sassou Nguesso made an announcement that he would form a new government.
This information was made public on Thursday in a statement issued by the country’s Presidency.
Mouamba announced his resignation along with the rest of his cabinet.
The central African nation has been struggling economically since a 2014 drop in oil prices.
In his speech, he acknowledged the real and worrying economic situation the country is currently facing and called for new leadership.
Denis Sassou Nguesso also promised that the new cabinet would revive the country’s economy even as the country concludes a structural adjustment programme with the International Monetary Fund.
Congolese journalists posted images of a presidential letter confirming Mouamba's resignation
No date has however been given for the formation of the new government, which also comes in the wake of the recent parliamentary elections.
Nguesso’s Congolese Party of Labour (PCT) won the majority seats.