Ruto was hosted by President Joe Biden last week on the first state visit to the United States by an African leader since 2008 and the first by a Kenyan leader in two decades.
Controversy has swirled over the cost of the trip, as ordinary Kenyans struggle with the high cost of living and a raft of tax hikes and new levies imposed by Ruto's government.
Local media reports said he had chartered a Boeing 737-700 business jet for the visit, which saw him secure several lucrative deals with the United States.
But Ruto scoffed at reports he had spent as much as 200 million Kenyan shillings ($1.5 million) on the plane, saying: "I am not a mad man."
"I am a very responsible steward," he said at a national prayer meeting in Nairobi on Thursday. "There is no way I can spend 200 million.
"Let me disclose here — that it cost the republic of Kenya less than 10 million (about $76,000)."
He said he had asked his office to book a flight on the national carrier Kenya Airways when he was told the cost of a private plane would be about 70 million shillings.
But friends then pitched in, Ruto said, without identifying them.
"I said I am not ready to pay more than 20 million. They said bring 10 million, we will give you the plane."
Previously Ruto has insisted that the cost of the private plane was less than using Kenya Airways.
He took office in 2022 promising to ease the lot of ordinary people.
But his cash-strapped government has since imposed a raft of austerity measures and Ruto has often said Kenyans needed to "tighten our belts" and live within their means.
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