A new global fund is being launched to help developing countries fend off challenges to tobacco control measures by cigarette makers, reports BBC.

The $4m (£2.7m) fund is a joint effort by Bloomberg Philanthropies and the Bill and Melinda Gates Foundation.

They say tobacco control gains are being put at risk by the industry's use of trade agreements and litigation.

But tobacco companies argue they are protecting investments, including intellectual property rights.

The fund has been launched in Abu Dhabi at an international conference on tobacco control.

Mr Gates added: "Country leaders who are trying to protect their citizens from the harms of tobacco should not be deterred by threats of costly legal challenges from huge tobacco companies."

Both philanthropic organisations hope the initial investment will grow, with other donors joining the effort.