The planned deal, published on the Russian government's website Wednesday, outlines a "logistical support centre" to be set up in Sudan where "repairs and resupply operations and rest for crew members" can take place.

Its capacity will be capped at 300 military and civilian personnel and four ships, including nuclear-powered vessels, the text added.

The base will stand on the northern outskirts of Port Sudan, according to coordinates named in the detailed document.

Russia will also gain the right to transport via Sudan's ports and airports "weapons, ammunition and equipment" needed for the base to function.

The deal is slated to stand for 25 years -- as long as neither party objects to its renewal.

So far Russian authorities have not named a date for the accord to be signed with Khartoum.

Moscow has in recent years turned its eyes to Africa as it renews its geopolitical clout.

It has wooed Sudan with military and civilian nuclear cooperation, signing a deal between the countries' armed forces in May 2019 set to last seven years.

In January last year Russia acknowledged, as a political crisis reached its peak in Sudan, that its military advisors had already been on the ground "for some time" alongside forces loyal to the government.

Former Sudanese president Omar al-Bashir asked President Vladimir Putin to "protect" his country from the US when he visited Russia in 2017.

He said military cooperation should be stepped up to "re-equip" Sudan's armed forces.