Whitbread will take up her role in December ahead of current chief executive, Baroness Jo Valentine, stepping down at the end of the year.
Until December 2015, Whitbread led Save the Children International, successfully bringing together all 30 of the Save the Children organisations, who helped 62 million children in countries around the world last year, to create a joined-up US$2bn operation and global campaigning force.
Before moving into the non-profit sector, she was previously managing director at Thomson Financial and has a background in technology marketing, holding management positions with Rio Tinto and a venture-funded start-up, Cortex.
Whitbread said: “London First was founded by visionary business leaders to propel London to the top of the global charts. Post referendum, we need another injection of sustained business leadership to keep us there.
“London First has proven that good business leadership is good for society and I’m excited at the prospect of working with John and what I hope will be a powerful alliance of leaders, to make a difference for my city at this critical time.”
Jasmine is also a non-executive director of BT plc and Standard Chartered plc.