Britain's Court of Appeal has ruled that judges may sentence people convicted of the most serious crimes to life in prison with no possibility of parole.

The judgment comes after the European Court of Human Rights said Britain should review the policy.

Five British judges led by Lord Chief Justice John Thomas said handing out such sentences in "rare and exceptional" cases was compatible with the European Convention on Human Rights.

There are about 50 prisoners in Britain serving "whole-life" sentences.

The appeals court dismissed challenges from two convicted murderers and ordered that one of them, triple killer Ian McLoughlin, have his 40-year sentence increased to life.

Sentencing of the killers of British soldier Lee Rigby, who were convicted in December, was put on hold until Tuesday's court ruling.