BRUSSELS - Environmental campaign groups lodged a complaint against the European Commission on Tuesday, accusing the EU executive of moving ahead with an overhaul of water protection and management laws without enough evidence.

The complaint is the latest by environmental groups over the European Union's efforts to simplify and scale back policies, a strategy known as the EU "omnibus", which responds to complaints from industries who say burdensome laws hurt their competitiveness with global rivals like the US and China.

The complaint concerns a Commission plan to revise the EU's main water legislation this year, in part in response to concerns by mining and metals companies that say the law's environmental safeguards are delaying permits for new critical raw materials mines and other industrial projects.

In a complaint filed with the European Ombudsman — the EU's independent watchdog — the World Wildlife Fund, the European Environmental Bureau and three other groups said the Commission had failed to sufficiently gather evidence and consult stakeholders before announcing the planned revision.

This failure amounted to maladministration, they said.

"Their cumulative effect amounts to a flagrant deviation from established due process, one that materially affects citizens' rights," the NGOs said. They argued that the EU water laws are not the reason new mines struggle to get permits, and do not need revising.

A Commission spokesperson said it had not yet been notified of the complaint, but that it would continue to engage with stakeholders as it prepares to revise the water laws.

"The Commission has been engaging in a transparent and inclusive dialogue with member states and stakeholders, and is currently assessing the input from stakeholders," the spokesperson said.

The Ombudsman will now decide whether to open an inquiry into the complaint. That process can take a few weeks, a spokesperson for the watchdog told Reuters.

The EU watchdog does not have enforcement powers, but rather makes recommendations that can affect future EU lawmaking, and increases scrutiny of the Commission.

Last year, the Ombudsman obliged the Commission to publicly explain why it had fast-tracked other proposals to curb sustainability laws, and not assessed whether the changes complied with Europe's climate change commitments.