A US-based team of financial forensic specialists is criticising the Kenyan government for not investigating South Sudan leaders' purchases of luxury homes in Nairobi.

The Sentry, a non-governmental investigative unit, noted on Tuesday that in 2016 its analysts had publicly identified high-priced properties in both Kenya and Uganda acquired by South Sudanese involved in a civil war that has killed tens of thousands and pushed millions out of the country or to the brink of starvation.

These homes in exclusive Nairobi and Kampala neighbourhoods may have been bought with the proceeds of corruption, The Sentry said two years ago and repeated on Tuesday.

“What will it take for Kenyan and Ugandan officials to investigate and then seize houses and other assets determined to be the proceeds of corruption in order to apply desperately needed pressure on South Sudan’s peace spoilers?” the NGO asked.

South Sudan President Salva Kiir owns a family home in Nairobi's upscale Lavington neighbourhood, as does South Sudan rebel chief Riek Machar, The Sentry says.

Paul Malong, former chief of staff of the South Sudan army, maintains a $2 million mansion in the gated Nyari Estate, the group adds, noting that Mr Malong was paid about $45,000 a year in his military leadership position.

Mr Malong, who led an army accused of massive human rights violations, also owns two luxury homes in Uganda, The Sentry states.

The group's contention that Kenyan and Ugandan authorities have failed to investigate possibly corrupt international dealings coincides with a visit to both countries this week by a US Treasury Department official who heads a financial intelligence unit.

Sigal Mandelker, a Treasury under-secretary, is urging officials in Nairobi and Kampala to close loopholes that allow transfer of illicit funds from South Sudan.

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