Insurance giant AXA has announced a quadrupling of its 2020 green investment target from $3.53 billion to $14.13 billion as the company's CEO warned more than 4 degrees Celsius of warming this century would make the world "uninsurable."

Launched at the One Planet Summit in Paris, Axa unveiled this week a raft of climate policy moves that also will see it further reduce its exposure to fossil fuel assets.

The company said the acceleration of its previous $3.53 billion in green investment target, originally set in 2015, was twice as high as the recent recommendation from former UNFCC executive secretary Christiana Figures that investors should aim to inject 1 percent of their assets into green and clean technology by 2020.

In addition, the firm said it will increase its coal divestment fivefold to reach $2.83 billion by moving its money away from companies "which derive more than 30 percent of their revenues from coal, have a coal-based energy mix that exceeds 30 percent, actively build new coal plants, or produce more than 20 million tonnes of coal per year."

It also announced plans to divest more than $824 million from main oil sands producers and associated pipelines, alongside the "discontinuation of further investments in these businesses," reasoning that oil sands are "an extremely carbon-intensive form of energy and a serious cause of environmental pollution."

Investors should aim to inject 1 percent of their assets into green and clean technology by 2020.

Bolstering its investment policy changes, AXA said it would be "inconsistent" to commercially support industries it is divesting from, announcing it would therefore stop insuring any new coal construction projects and main oil sands and associated pipeline businesses.

Highlighting AXA's influential 2015 decision to divest $588.85 million from companies which derive more than 50 percent of their revenues from coal, CEO Thomas Buberl said a "plus-4C world is not insurable."

"We have made some pioneering moves since 2015, notably by starting to divest from coal, setting an ambitious green investments target, and restricting our insurance business with the coal industry," he said in a statement. "Today, in the spirit of the Paris Agreement, we want to accelerate our commitment and confirm our leadership in the fight against global warming."

The move came as the Task Force on Climate-related Financial Disclosures (TCFD) 237 companies with a market capitalization of $6.3 trillion have given their backing to its climate disclosure guidelines since their launch this summer.

AXA is one of the company's to back the best practice guidelines, confirming it would be implementing them in its upcoming annual financial report.

Bank of England Governor Mark Carney, chair of the Financial Stability Board which appointed the TCFD, confirmed momentum behind the group's recommendations were growing fast during a panel session Dec. 12 at the One Planet Summit in Paris. He said support for the guidelines has more than doubled in the five months since they were launched.

ING plans to phase out its lending to individual coal-fired power plants by the end of 2025.

The news comes amid a slew of climate announcements from the financial sector as French President Emmanuel Macron hosts the one-day summit in Paris.

For example, Dutch bank ING also unveiled plans to further strengthen its coal policy.

The bank said it would no longer finance clients in the energy sector that are more than 5 percent reliant on coal-fired power in their energy mix. However, it explained it would support new clients in the sector with less than 10 percent reliance that have a strategy to reduce the coal percentage near to zero by 2025.

Moreover, ING plans to phase out its lending to individual coal-fired power plants by the end of 2025, according to the bank's vice chairman, Koos Timmermans.

"We realize that contributing to the Paris Agreement targets is also about making clear choices in what we'll no longer finance, especially when there are good alternatives available," said Timmermans. "We are taking this decisive step as part of our overall ambition to support the energy transition."

The news came as a host of sustainable investment groups launched a new initiative called Climate Action 100+, which brings together 225 global investors with more than $26.3 trillion in assets under management. The initiative will see the investors engage with 100 corporates estimated to be responsible for around 85 percent of total global greenhouse gas emissions, and call on them to embrace the TCFD recommendations and set out a strategy for addressing climate risks.