It is expected the monsoon season, starting in June, will make the conditions in the camps near the Burmese border more “lift-threatening”.

Heavy rains could also wash away makeshift shelters and cause fatal diseases to spread more rapidly.

The UK’s international development secretary Penny Mordaunt said: “The UK is leading the way to help vaccinate people against a deadly cholera outbreak, strengthen shelters, and provide vital food and water to vulnerable Rohingya families who have already been forced to flee their homes because of brutal violence and persecution.

“The Bangladeshi government must now use their expertise to ensure Rohingya families are saved from dangerous rains.”

The UK aid will provide medication, studier shelters, food, clean water and support for women to give birth safely, the Department for International Development said.

The additional funding takes the UK’s total support for the crisis since August 2017 to £129m. More than 600,000 people fled from Myanmar to Bangladesh as violence broke out when militants reportedly attacked government forces after decades of ethnic tensions.

According to UN estimates, 102,000 Rohingya people were living in areas at risk of flooding and 12,000 were at risk from landslides during the monsoon season, which starts in June.