The organisation confirmed they would not send athletes to the event, scheduled to take place from July 12 to 16, citing Kenya’s “critical” crime and terrorism rating, the highest possible, from the US State Department.

USATF conducted a risk assessment on the Kenyan capital, while consulting the security summary from the State Department.

The US have followed Australia, Britain, Switzerland, New Zealand and Canada in withdrawing from the event.

“Due to increased security costs and the fact that all athletes would be aged 18 and younger, USATF has decided not to hold a selection event nor to travel to the Championship,” USATF said in a statement.

“USATF is a strong supporter of ensuring the growth of track and field internationally, particularly among young people.

“We will continue to work with our IAAF colleagues to ensure appropriate and productive competitive opportunities for youth in the world.”

The decision from USATF has been met with criticism from Kenyan officials, with Government spokesman Eric Kiraithe telling The Standard that “terrorism is not a one-country problem”.

“In any case Kenya has in the past hosted big events and never failed to secure them,” he added.

“If they had concerns over insecurity or terrorism, they should have reached out to the Kenyan government.”

Al Shabaab, a militant group in Somalia opposed to the Somali government, have issued public threats to Kenya as a result of their military intervention in the nation.

Back in 2013, the group killed 67 people at Nairobi's Westgate Shopping Mall.

Those involved in a shooting at Garissa University College in 2015, where almost 150 people lost their lives, also claimed to be representing Al Shabaab.

"We had hoped that even after Great Britain’s withdrawal, USA would still support us but it’s disappointing that they have also followed suit,” Athletics Kenya chairman in charge of youth and development Barnaba Korir told Daily Nation.

“The President, Uhuru Kenyatta, should come out to address the issue and reassure the world since Kenya is bound to lose a lot.

“This is a blow to the championships yet the Sports Minister has continued to keep quiet."

The IAAF confirmed following a council meeting in Rio de Janeiro last year that the 2017 edition of the World U18 Championships would be the last.

The governing body announced they would “find a more appropriate competition structure for assisting the career development of U18 age group athletes”, which could include a series of events held on a regional basis.