Kenya's world half-marathon record holder Samuel Wanjiru has withdrawn from Sunday's Great Manchester Run after being denied a visa.
"It is outrageous to deny an internationally recognized runner like Wanjiru a visa," Athletics Kenya Secretary-General David Okeyo said.
"We do not know the reason behind this (decision), but it is surprising, especially because we have information he applied on April 15.
"We shall send a protest note to the mission after getting all the facts about the matter.
"We would like our athletes to be treated fairly around the world because they are our best ambassadors," he said.
Wanjiru, who is based in Fukuoka, Japan, announced late on Tuesday he had withdrawn from the 10 km race.
The race's elite athletes director, Matthew Turnbull said he regretted the development.
"It is frustrating to lose a star athlete through administrative procedures yet again, it is not as if Wanjiru applied just last week to come and run," elite race director Matthew Turnbull said.
Wanjiru had been tipped to challenge Ethiopian Haile Gebrselassie's 10 km world record of 27 minutes two seconds, set in 2002.
The field does include Eritrea's world cross country champion Zersenay Tadesse.