Third-ranked Cabinet minister Gerry Brownlee will represent the Government at the funeral of former British prime minister Margaret Thatcher.
There is a 2000-strong guest list for the event, including all of Britain's surviving ex prime ministers and representatives from around 200 states and international organisations, according to Downing Street.
A number of celebrities have also made the guest list - including singer Shirley Bassey and Top Gear presenter Jeremy Clarkson.
The dress code is full day ceremonial without swords, morning dress (black waistcoat and black tie) and medals and decorations may also be worn.
Will you be voting in this year's General Election?Related story: Map: Voter enrolment rates declining