The headmistress at Haberdashers' Monmouth School for Girls (HMSG) has been appointed principal at one of Canada's most prestigious girls' schools.

Helen Davy, who has been in charge at HMSG since 2008, will take up her new post a Havergal College in Toronto in April 2014 after a period of transition in Monmouth.

The school's governing body will now start the process of selecting a successor to Mrs Davy, aiming to consolidate HMSG's reputation as one of the UK's leading girls' schools.

Sheridan Swallow, chairman of the governing body, said: "We would like to take this opportunity to congratulate Mrs Davy on her impressive new appointment and to thank her for her strong leadership of HMSG over the past five years which has seen boarding numbers double and over 65 per cent of our leavers consistently gain places to Russell Group universities.

"We will now seek to find a strong successor who can build on our shared vision for this outstanding school."

Mrs Davy said: "I have thoroughly enjoyed my time at HMSG and will miss the wonderful girls and staff with whom it has been my great privilege to work.

"I am excited about my move to Canada and the opportunity to lead a school with over 1,000 students in such a vibrant city.

"I shall continue to work as normal during my final year in Monmouth to ensure every girl feels valued and supported at HMSG."