A statement by the trustees says the fund will become a "living memorial through helping those in need and distress".

The move has been approved by Diana's brother, Earl Spencer, despite his earlier calls to wind the charity up.

The Fund was criticised for allowing Diana's signature on tubs of margarine

The fund, which has raised £50m, will give a minimum of £4m to good causes every year.

Donations have poured into the Fund since Diana died with her companion, Dodi al-Fayed, in a car crash last August in Paris.

Earl Spencer, has in the past been a fierce critic of what he has called the fund's "tacky" merchandising deals, and set up a Diana Spencer memorial fund of his own.

The main memorial fund has come under attack particularly for allowing the princess's signature - its logo - to appear on tubs of margarine.

'Priority is to make a difference'

"The Diana, Princess of Wales Memorial Fund is to be a living memorial through helping those in need and distress, especially at the margins of society," the statement said. "It will continue this work indefinitely."

Among the groups receiving money will be land mine survivors, a cause espoused by the princess in the months before she died.

"The trustees' overriding priority is to make a difference to the lives of these people," the statement said.

The trustees have already made grants of £13m and they pledged to give special weight to applications from those who would "find it difficult to obtain recognition and support from sources other than the fund".

While she was married to Prince Charles, the heir to the British throne, Princess Diana was associated with more than 100 charities, but after her divorce in 1996, she kept her connection with only six.