Crowds have begun to gather around the cenotaph in Whitehall ahead of the annual service to pay tribute to those who have died in major conflicts.
The Queen will lay a wreath in memory of those who lost their lives.
Prime Minister David Cameron and other party leaders will also leave tributes at the memorial.
The Queen and the Duke of Edinburgh will attend the Royal British Legion Festival of Remembrance tonight as the nation begins three days of honouring those who have lost their lives in conflicts past and present.
Other members of the Royal Family will also be present for the event at the Royal Albert Hall, which will feature performances from pop stars James Blunt - a former army officer - and Katie Melua, plus the tenor Alfie Boe and new group the Poppy Girls.
The audience of 4,000, including Legion supporters and military families, will be joined by an estimated 5.2 million viewers on television.