The company said the process to recruit a successor is “well advanced” and will be completed in due course.
Waterfield will relocate to the UK from Dubai following his resignation, specifying family reasons.
He said: “I have every confidence that the business will go from strength to strength.
“I wish everyone at FPI and our distribution partners all the very best for the future.”
In May, FPI announced that it was targeting non-resident Indians as part of a wider focus on specific expat client groups following the appointment of Philip Cernik as head of global expat propositions.
The company has produced customer-focused guides aimed at helping non-resident Indians (NRIs) with financial planning, and it plans to launch similar technical support initiatives for three other customer segment groups later this year.
Cernik added at the time that the products were also being tailored to particular client needs, for example in the case of NRIs who may be considering a return to their home country.