Ambassador Amayo presented his credentials to President Donald Trump at a ceremony at the White House that took place more than a year after President Kenyatta had appointed him to the post.
In their remarks on Friday, President Trump and Ambassador Amayo both cited the recent launch of negotiations that could culminate in a historic Kenya-US free trade and investment agreement.
Mr Amayo succeeds Robinson Njeru Githae as Kenya's US envoy. Mr Githae had held that job for five years prior to being transferred to lead the Kenya embassy in Austria.
New York,
Lazarus Amayo on Friday formally took up his duties as the 18th Kenyan ambassador to the United States.