Moving 4,500 British Scouts from an international event into hotels in South Korea will affect activities for five years, the UK Scouts chief executive has said.

Matt Hyde said poor sanitation and insufficient medical services led to the UK contingent being moved from the campsite at Saemangeum to Seoul.

“We feel let down by the organisers,” Mr Hyde said.

Hundreds had fallen ill at the World Scout Jamboree amid 35C (95F) heat.

Local media has reported that Scouts from the UK were among those affected by heat exhaustion. The US and Singapore have also pulled their teams from the event.

Jamboree organisers announced on Monday that all Scouts will be pulling out of the campsite due to an expected typhoon.

The British group, the largest in attendance, arrived at the campsite near the town of Buan last week but started moving back to the South Korean capital on Saturday.

Mr Hyde said the UK Scouts had raised repeated concerns but while there were some improvements it was “too little too late”.

Conditions at the site breached four red lines around a lack of shade, lack of food for those with dietary needs, poor sanitation and insufficient medical services, he added.

“We feel let down by the organisers because we repeatedly raised some of these concerns before we went, and during, and we were promised things were going to be put in place and they weren’t,” he said.

“If you can imagine [toilets] that are being used by thousands and thousands of people that are not being cleared with the regularity you would expect, you can imagine the sort of things that people were seeing.”

Relocating 4,500 people has cost the Scout Association well over £1m, the chief executive said.

“We had commitments to those reserves that will of course mean that we can’t now do things that we wanted to do over the next three to five years,” he said.

The jamboree, described as the world’s largest youth camp, gathers Scouts from around the world every four years, each time in a different country.

Most of those attending are aged between 14 and 18, and 155 countries are represented in South Korea.

This is the first jamboree since the pandemic and is due to run until 12 August.