Ruto posted a picture of himself on social media meeting RSF chief Mohammed Hamdan Daglo at the Kenyan president's official residence in Nairobi.
Ruto said he "appreciates the commitment" shown by General Daglo to "ending the conflict" in Sudan.
Ruto referred to the ceasefire talks led by an eight-member East African bloc of states to end the war that has been raging since mid-April.
"The ongoing Intergovernmental Authority on Development (IGAD) talks should bring about a political settlement that would effect a lasting peace in the country. We are looking forward to nothing but a peaceful resolution and a stable neighbour," Ruto posted on X.
Held talks with the RSF Leader General Mohamed Hamdan Dagalo, State House, Nairobi. — William Samoei Ruto, PhD (@WilliamsRuto) pic.twitter.com/2FpmtlMPg2January 3, 2024
The RSF is a quasi-army that emerged from militias in the Darfur region and is led by Daglo.
The group has been accused of looting, mass killings, rape and ethnic cleansing.
In the ongoing power struggle, the RSF is fighting against the forces of the Sudanese de facto ruler Abdel Fattah al-Burhan.
The RSF was recently able to get the upper hand over the Sudanese army in some areas of the country, including in al-Jazirah state, which is considered Sudan's breadbasket.
Daglo has been on a regional tour since last week.
He recently met with Sudan's former civilian prime minister Abdulla Hamdok in Ethiopia to discuss a plan to end the war.
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