Northern Ireland Secretary Mo Mowlam yesterday defended her controversial decision to invite Sinn Fein leaders to a royal garden party at Hillsborough Castle later this week.

Challenged by Shadow Northern Ireland Secretary Andrew Mackay in the Commons, Ms Mowlam said: ''It's normal to invite all political parties to the garden party.

''All the parties that signed up to the Good Friday agreement have been invited. That's the only fair and just way to do it.

''We can't expect people to participate in the Assembly together and then say we judge for ourselves different standards.''

Ms Mowlam was answering questions after making a statement on the outcome of the referendums on the peace agreement in Northern Ireland and the Irish Republic.

Sinn Fein leaders Gerry Adams and Martin McGuinness have turned down the invitation to the party, which will be attended by the Prince of Wales.