The government faces legal action for failing to protect people from discrimination at work, throwing doubt on any proposals for a new law on equality.

The European commission has said parts of UK law, including provisions on sexual orientation and disability, are inadequate. It could refer the situation to the European court of justice.

The claim, set out in two reasoned opinions sent to the government last month, includes a warning that the law that applies to faith-based organisations, schools and adoption agencies allows too much scope for discrimination on grounds of sexual orientation.

"This could be difficult for the government," said Robin Allen QC, head of Cloisters chambers. "The extent to which religious organisations are exempt from the rules of sexual orientation discrimination is a particularly difficult issue. The government will certainly resist any strengthening to the current law in an election year."

Other parts of UK law singled out by the EU's equal opportunities commissioner include the lack of a ban on "instructions to discriminate", where a person is discriminated against because of the actions of a third party, and the lack of clear provisions for class actions.