Warren Buffett said Wednesday he is resigning as a trustee of the Bill and Melinda Gates Foundation while making a $4.1 billion donation to the organization as well as four others.

The 90-year-old business magnate did not give a reason for the resignation, which comes about seven weeks after Bill and Melinda Gates announced their divorce.

Buffet, whose wealth is currently estimated by Forbes at $104.4 billion, signaled continued support for the Gates Foundation in a statement.

"My goals are 100 percent in sync with those of the foundation, and my physical participation is in no way needed to achieve these goals," he said in a statement from his company, Berkshire Hathaway.

"For years I have been a trustee -- an inactive trustee at that -- of only one recipient of my funds," Buffett said. "I am now resigning from that post, just as I have done at all corporate boards other than Berkshire's."

Warren Buffett signaled strong support for the Bill and Melinda Gates Foundation even as he said he was resigning as a trustee
Warren Buffett signaled strong support for the Bill and Melinda Gates Foundation even as he said he was resigning as a trustee GETTY IMAGES NORTH AMERICA / Paul Morigi

Buffett said his latest donations are in line with a 2006 pledge to distribute all of his Berkshire stock to philanthropy.

"With today's $4.1 billion distribution, I'm halfway there," Buffett said, adding that he now holds around 240,000 Berkshire shares worth about $100 billion.

Berkshire Hathaway signaled in May that it plans to name Greg Abel as chief executive when Buffett, the conglomerate's longtime chief, eventually exits. But the firm has not given a timeframe for a transition.

Scrutiny of Bill Gates has risen after the couple announced in early May they were divorcing after 27 years.

Some have questioned Bill Gates' relationship with Jeffrey Epstein, a convicted sex offender who died by suicide while awaiting trial on trafficking charges.