Tesla chief executive Elon Musk donated about 5 million shares of company stock worth roughly 5.7 billion dollars (£4.2 billion) to an unidentified charity in November, according to a regulatory filing.

The shares were donated from November 19 to 29, the filing with the US Securities and Exchange Commission said.

In late October, Mr Musk, the world’s richest man, tweeted that he would sell 6 billion dollars in Tesla stock and give the money to the United Nations World Food Programme (WFP) if the organisation would describe how the money would solve world hunger. But the filing did not name any recipients for the donation.

David Beasley, WFP executive director, said in a statement on Tuesday that the organisation has not yet received anything from Mr Musk.

“There are millions of people around the world on the brink of starvation. Whether WFP receives any of this money is yet to be seen, but I am excited to hear that Elon is engaged. This is an amazing and great first step,” Mr Beasley said in a statement.

In a separate filing, Mr Musk reported that as of December 31 he holds 231.7 million shares of the electric vehicle and solar panel maker’s stock, or 21.2% of the company’s total value.

The amount includes 172.6 million shares held by his trust and options to buy another 59.1 million within 60 days of December 31.

Last November, Mr Musk began selling shares, which he said on Twitter would go to pay for his tax obligations on stock options that are part of his all-stock compensation package.

Analysts estimate his tax obligation at 10 billion to 15 billion dollars (£7.4 billion to £11.1 billion).

So far he has sold more than 15 million shares worth roughly 16.4 billion dollars (£12.1 billion).

Mr Musk had written on Twitter that he would sell 10% of his stake in the company. With the sales in late December, he is close to that figure.