An historic explosive device was found near the Cutty Sark in Greenwich and a section of the River Thames was closed off while police investigate.
The device, thought to be a hand grenade, could safely be disposed of in a controlled explosion, the Metropolitan Police added.
The Queen has stepped on board the restored Cutty Sark tea clipper on a visit to Greenwich, south east London.
- The world's last remaining tea clipper, it is now 143 years old
- A restoration project for the vessel cost £50 million
- The 2007 fire was caused by a vacuum cleaner that had been left on
- The clipper is now displayed more than 11ft above its dry berth in Greenwich, south east London
- The space under the three-masted vessel is home to an interactive museum
- Most of the fixtures and fittings were removed before the fire so visitors can still see many original features on deck
- The Duke of Edinburgh has a long association with the ship and co-founded the Cutty Sark Society in 1951 to safeguard the vessel
- He came to Greenwich soon after the fire to assess the damage for himself and passed on advice gained from the fire at Windsor Castle in 1992
The Cutty Sark has been reopened five years after it was hit by a devastating fire:
The Queen has reopened the Cutty Sark following a £50 million makeover for south east London's maritime landmark, reports ITV News' Royal Editor Tim Ewart.
The Cutty Sark, the world's last remaining tea clipper, has been reopened by the Queen five years after it was ravaged by a fire.
The maritime attraction, which was first opened by the Queen 55 years ago, has undergone a £50 million restoration.
The Queen also made her first visit to Gloriana, the new Royal Row Barge.
The Queen and the Duke of Edinburgh will be in Greenwich today to reopen the tea clipper the Cutty Sark after it was severely damaged in a fire in 2007.
ITV Daybreak's Tiffany Royce has been in Greenwich to get a preview of the newly restored ship, speaking to Cutty Sark trustee Chris Roberts.
During their tour of Greenwich - which has been made a royal borough to mark the Queen's Jubilee - the Queen and Philip will visit the nearby National Maritime Museum.
The Queen will open a new exhibition - curated by historian David Starkey - which explores the relationship between the monarch, the City of London and its people through the River Thames.
The major exhibition celebrates her Diamond Jubilee and the Museum's 75th anniversary and features paintings, manuscripts and other artefacts.