Britain’s Queen Elizabeth II said on Monday that she is “deeply saddened” by the severe flooding in Pakistan that has claimed more than 1,150 lives.

“I am deeply saddened to hear of the tragic loss of life and destruction caused by the floods across Pakistan,” the queen wrote in a letter to the country’s President Arif Alvi.

“My thoughts are with all those who have been affected, as well as those working in difficult circumstances to support the recovery efforts,” the queen said.

She added that the UK stands in solidarity with Pakistan as it recovers from these “terrible events.”

Monsoon rains that began in June have unleashed the worst flooding in over a decade, washing away swathes of vital crops and damaging or destroying more than 1 million homes.

Prince Charles also sent a letter to Alvi in which he paid tribute to the government of Pakistan, the military and emergency services, and “the countless volunteers and aid agencies who are working tirelessly to save lives and support those in need.”

The prince also made a donation to Islamic Relief UK for the flood-ravaged country. The charity thanked him for supporting its Pakistan Floods Appeal.

Authorities and charities are struggling to accelerate aid delivery to more than 33 million people affected, a challenging task in remote areas as roads and bridges have been washed away. Pakistan needs more than $10 billion to repair and rebuild infrastructure damaged by the monsoon rains that have caused devastating flooding, the country’s Planning Minister Ahsan Iqbal said Tuesday.