It is everyone's concern, in as much we should all be aware of atrocities, but this is a civil war, and the "official" Sudan government doesn't want outside help beyond the Russians - to whom it's giving space for a naval base:
Sudan says plan for first Russian naval base in Africa will go ahead
A plan for Russia to establish its first naval base in Africa will go ahead, Sudans foreign minister has confirmed, after years of delays over the Red Sea military port.
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Sudans military and civilian leaders dragged their feet on moving ahead with the deal due to lingering differences over its terms. The civil war that started in April 2023 between the army and the paramilitary Rapid Support Forces further complicated relations between Russia and Sudan, as the Russian-backed Wagner group threw its weight behind the RSF while the Kremlin appeared to back the Sudanese army.
Russia was playing both sides, said Samuel Ramani, an associate fellow at the Royal United Services Institute thinktank and the author of a book on Moscows engagements with Africa. Since the death of Yevgeny Prigozhin, the Wagner mercenary groups leader, the Kremlin had incrementally deepened ties with the Sudanese army, Ramani added.
Last April, Russias deputy foreign minister, Mikhail Bogdanov, visited Sudan and pledged uncapped support for its army. Russia has also backed Sudan at the UN security council, where it vetoed a resolution calling for a ceasefire for humanitarian reasons, a move the UK foreign secretary, David Lammy, called a disgrace.
https://www.theguardian.com/world/2025/feb/13/sudan-first-russian-naval-base-in-africa-go-ahead