More than 100 Iraqis have won a UK Court of Appeal battle as they seek to open a new public inquiry into allegations of torture by British soldiers during the 2003 Iraq war.

Three appeal judges ordered the UK defence secretary, Philip Hammond, to open an inquiry. Previously, the High Court had supported government claims that an inquiry was not necessary.

The appeal judges found that other inquiries had failed to fully meet Article 3 of the European Convention of Human Rights, which protects against inhumane and degrading treatment.

About 128 Iraqis complained of torture and inhumane and degrading treatment by British soldiers between March 2003 and December 2008.

The defence secretary has until 30 November to decide whether to challenge the ruling in the Supreme Court.