NEW YORK (Reuters) - The estate of McDonald's Corp. heiress Joan Kroc will donate more than $1.5 billion in cash to the Salvation Army, in one of the largest individual charitable gifts ever, the charity confirmed Tuesday

A statement from the Salvation Army said the exact amount wouldn't be known until the completion of the administration of the estate.

"We are obviously thrilled, but genuinely humbled by the exceptional generosity of Joan Kroc," said spokesman W. Todd Bassett. "We recognize the deep sense of trust she has placed into our hands with this gift. Mrs. Kroc was a wonderful friend of The Salvation Army and we miss her. Her passion for children and families, and her hope for community peace will live on forever through this incredible gift."

Kroc, the billionaire widow of McDonald's (MCD: Research, Estimates) founder Ray Kroc and one of the hamburger chain's largest individual shareholders, died in October at the age of 75 following a short illness with brain cancer.

Half of the donated money is to go toward construction of 25 to 30 new community centers, which would provide recreational and educational facilities to the public. The other half is supposed to go into an endowment, from which the interest will be used to help offset operating costs of the centers.

Kroc gave $100 million to the Salvation Army in 1998 to build a community center, which opened last year. Also in 1998, she donated $25 million to the University of San Diego to establish an Institute for Peace and Justice.

In November, the Kroc estate donated $200 million to National Public Radio.