New York state’s attorney-general is investigating ExxonMobil over its reporting of its asset valuations, widening the investigation launched last year into the company’s disclosures on climate change.

Eric Schneiderman is looking into why Exxon has not followed its peers in the oil and gas industry in taking large non-cash charges for writedowns in the value of its assets, according to an individual briefed on the investigation.

Mr Schneiderman's office would not confirm the investigation, which was first reported by the Wall Street Journal.

The move builds on the attorney-general’s ongoing inquiry into whether Exxon misled investors and the public over the risks of climate change. Last year, he sent a subpoena to the company seeking emails, financial records and other documents going back to the 1970s, relating to the company’s statements on climate and its support for outside groups.

Exxon said in a statement that its results were reported in accordance with the standards set by the Securities and Exchange Commission, the financial regulator, and the Financial Accounting Standards Board, the private sector body that sets reporting rules. – Copyright The Financial Times Limited 2016