Shell’s former chair calls fossil fuel divestment ‘rational’

deep water oil rigMark Moody-Stuart, former chairman of Royal Dutch Shell, lends credit to divestment movement by calling oil stock selling 'rational.'

The former chairman of Royal Dutch Shell said selling oil stocks is a "rational" response to the failure of the oil industry to take meaningful action on climate change.

He is the latest to lend support to the growing campaign for investors to dump shares of fossil fuel companies.

"Divestment is a rational approach," Mark Moody-Stuart was quoted by the Guardian as saying during a recent dinner in London. "If you think your money can be used somewhere else, you should switch it. Selective divestment or portfolio-switching is actually what investors should be doing."

Moody-Stuart starting working as a geologist at Shell in the 1960s. He worked his way up to being Shell's chairman from 1998 to 2001. Shell (RDSA) is the world's largest publicly-traded oil company by revenue.

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The movement for investors to sell stocks in fossil fuel companies -- oil, gas and coal -- is growing. The argument is being made on both moral and financial grounds.

Morally, advocates say that it's unethical to invest in an industry that's contributing so much to climate change.

Financially, proponents argue that it's a smart move because the value of these companies is largely based how much oil and coal they own in the ground. It's quite likely that some or all of those assets will never be able to be burned in a warming world, especially if governments enact stronger policies to combat climate change.

"The fact that even old oil company executives understand [divestment's] necessity is fairly stunning," Bill McKibben, an environmental activist and leader of the divestment movement.

The fossil fuel divestment push began in the environmental community, but it's been gaining more mainstream traction. Last fall, Norway's largest pension fund said it will sell all its coal shares.

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A year ago, Stanford University said it would no longer invest in coal companies after students and faculty petitioned the school to take action against climate change. In April, Syracuse University went a step further and said that it will no longer invest in publicly-traded companies whose primary business is fossil fuel extraction.

Perhaps the most high-profile divestment to date came in September when the $860 million Rockefeller Brothers Fund shocked the world by committing to dump all its holdings in fossil fuels. The Rockefeller family made much of its fortune off the Standard Oil Company at the turn of the 20th Century.

-- CNNMoney's Heather Long contributed to this report

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