Five investors have been removed from the United Nations-backed Principles for Responsible Investment (PRI).

The PRI said on Monday four asset managers and one asset owner would be delisted. This is the first such move by the group for those failing to meet its minimum requirements.

The PRI has amassed more than 3,000 signatories managing in excess of $100 trillion in assets since it was launched in 2006 and membership is increasingly seen as crucial for asset managers pitching for mandates from pension schemes.

Members of the PRI were told in 2018 they had two years to reach a new set of minimum requirements.

BPE, the private banking arm of France’s La Banque Postale, is the largest, with assets the PRI put at around $5 billion.

Stichting Gemeenschappelijk Beleggingsfonds FNV (GFB) which is part of the biggest Dutch labour union, Indonesia’s Corfina Capital, U.S.-based Primary Wave IP Investment Management and French-based Delta Alternative Management, which reported assets of between $40 million to $310 million, were also removed, the PRI said.

The delistings follow criticism in recent years that the PRI was not doing enough to ensure members lived up to the principles, including to embed environmental, social and governance-related issues in their investment decision-making.

This first round of exclusions may not satisfy all its critics given it affects mainly small firms, while some much larger signatories are being challenged for perceived inaction when engaging with companies on climate change.

The new standards require members to have a responsible investment policy covering at least half of all managed assets, staff responsible for implementing it and senior-level oversight.

The PRI did not say which standard the delisted firms failed.

The PRI said it now plans to toughen membership requirements further and will launch a consultation at a meeting on October 21.

(with inputs from Reuters)