LONDON (Reuters) -A call by Donald Trump to ditch quarterly corporate reporting has received cautious support from an unlikely source: international investors pushing business to do more on longer-term sustainability issues, many lambasted by the U.S. president.

Trump on Monday called for companies to shift to six-monthly updates, adding his voice to those of business heavyweights including Berkshire Hathaway Chair Warren Buffett and JPMorgan ( JPM ) CEO Jamie Dimon, who have argued in the past that short-termism harms the economy.

Abandoning quarterly reporting would see the world's biggest economy and the deepest capital market join a global shift away from the practice and could help those investors pushing boards to do more on issues such as climate change that are set to increasingly impact corporate value.

"Responsible investment people have never been advocates of quarterly reporting, since it tends to encourage a greater focus on trading and less on good ownership," said David Pitt-Watson, corporate governance expert and Fellow at Cambridge University's Judge Business School. 

Sustainability issues have been under attack by Trump since he began his second term earlier this year, though, including through a move to nix a rule that would have pushed companies to disclose climate-related data.

For many investors in Europe and elsewhere, that data is exactly what they want to see.

"We want companies to consider the material impact of their strategies on a long-term view and plan accordingly to mitigate any sustainability-related risks, so if moving away from quarterly reporting can help achieve this without impacting transparency and disclosure then it could be positive," said Nick Duncan, Sustainable Investment director at investor Aberdeen, which manages more than 500 billion pounds ($682 billion).

"Especially if the reduced quarterly reporting burden encouraged companies to maintain or enhance the current level of sustainability-related reporting."

That aside, the move had a clear win in that it would reduce the amount of time companies spend in 'closed period' ahead of results - typically a month - during which investors are not allowed to speak with them, he added.

Changing the securities law that stretches back decades would mark a sea-change for the world's biggest capital market, where more than 4,000 companies with a combined market capitalisation of more than $60 trillion trade publicly.

Overseas investors have long been used to dealing with six-monthly updates from companies in many European Union countries, Britain, Australia, New Zealand and Hong Kong.

Other than the U.S., China is the biggest equity market still requiring it by law although local stock markets in countries such as Japan and Germany still demand it as a condition of listing, or listing on the premium market.

For investors in Britain - which made the move to interims more than a decade ago, alongside the EU - it had helped bolster sustainability efforts, said Andrew Ninian, director of Stewardship, Risk and Tax at The Investment Association, the UK trade body for the investment industry.

"Moving away from mandatory quarterly reporting has given companies greater flexibility to focus on long-term investment decisions, strategy and reporting rather than management of short-term targets."

Despite that, some investors cautioned action would be needed to shore up investor protections.

"Although semi-annual reporting works in some countries, such as the UK and Australia, there are structural differences that make the U.S. context more challenging," said Hayley Grafton, Senior Sustainable Investment analyst at UK investor Edentree Investment Management.

Examples of potential gaps include around profit warnings. In Britain, they are treated as regulatory disclosures while in the U.S., they are not a regulatory requirement and updates can be withheld, she said.

And unlike in Australia, where companies must provide continuous disclosure of material information and are expected to issue trading updates where performance diverges from guidance, the U.S. has no equivalent to this outside earnings guidance.

Despite the need for safeguards, which Grafton said also included monitoring of the impact on transparency and the cost of capital, Pitt-Watson said the move could help sustainability investors.

"As Trump says, the former has knock-on effects distracting management. So a move to half-yearly reporting might support long-term, value-adding management. I think many of us think that is a good thing."

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