A man was tasered by police outside Buckingham Palace at 11.55am
A collection of 10,000 gems is going on show to the public at Buckingham Palace to mark the Queen's 60 years on the throne.
Four people have been charged after scaling the gates of Buckingham Palace and chaining themselves to the railings of Buckingham Palace.
The Queen is in "good spirits" and "good health" besides the symptoms of gastroenteritis, her spokesman has said. He added:
This is a precautionary measure. She was not taken into hospital immediately after feeling the symptoms. This is simply to enable doctors to better assess her.
The Queen's sickness was first announced on Friday, and she spent yesterday resting at Windsor.
Her Majesty had been due to attend a Welsh military celebration in Swansea during the country's St David's Day celebrations on Saturday, but was forced to cancel the plans.
The Queen, who is 86, has undertaken a number of engagements during the last week.
On Tuesday she met the Archbishop of Canterbury at Buckingham Palace, and on Thursday she presented a host of Olympic stars with honours during an investiture ceremony.
The Queen will no longer travel to Rome this week after being admitted to hospital, Buckingham Palace has said.
The Italian presidency has confirmed the scheduled two-day visit has been cancelled due to "health reasons", Reuters reported.
The Queen is in hospital suffering from gastroenteritis, Sky News has reported.
London 2012 medallists Natasha Baker and Louis Smith have updated their Twitter profiles with their new titles.
They were formally presented with their honours by the Queen earlier today.
Louis Smith has tweeted this photo of himself "chilling" with his MBE:
Olympic gymnast Louis Smith has tweeted about being awarded with an MBE this afternoon.
Sophie Hosking, from Wimbledon, was also awarded an MBE for services to rowing.
The athlete, who won gold in the Lightweight Women's Double Scull at London 2012, learned to row at school in Kingston and now trains at the London Rowing Club in Putney.
Paralympic champion Natasha Baker almost didn't make it in time to receive her MBE this morning.
She tweeted from her car on the M4, panicking about the traffic. But thankfully she got to Buckingham Palace in time to receive her gong from the Queen.
Tempted to get Jordan (scooter) out and drive to Buck Pal! Think she would be faster than this traffic! Don't think I'm going to get there!From @NBakerParaRider on Twitter:
The Olympic gymnast Louis Smith has received his Member of the British Empire (MBE) medal in an investiture ceremony at Buckingham Palace.