A State Department official said on Thursday that the United States respects but regrets Nasa leader Raila Odinga's announced intention to withdraw from the scheduled October 26 presidential election.
Responding to a Nation query, the official also said Mr Odinga is welcome to visit the US.
Sections of the Kenya media reported earlier this week that Mr Odinga had been denied a visa to travel to the United States.
That claim was attributed in those reports to State House Director of Digital Communications Dennis Itumbi.
Asked whether Mr Odinga had been blocked from visiting, the State Department official said, "It is our understanding that nothing prevents Raila Odinga from getting on a plane and flying to the United States."
FREE AND FAIR ELECTION
Mr Odinga is in London, where he is expected to give an address on Friday at Chatham House, Royal Institute of International Affairs.
In its email message to the Nation, the State Department reiterated that the US does "not back any part or candidate" in Kenya.
"We remain committed to supporting a free, fair and credible election that is consistent with Kenya's Constitution, current laws, and institutions," the official said.
"We respect the right of Nasa presidential candidate Raila Odinga and deputy presidential candidate Stephen Kalonzo Musyoka to withdraw from the Kenyan election scheduled for October 26, but we regret their decision to do so," the official added.