U.S. President Donald Trump arrives at The Grove hotel and resort in Watford. (AP Photo/Evan Vucci) (Image: Copyright 2019 The Associated Press. All rights reserved)
US President Donald Trump and UK Prime Minister Boris Johnson were among those in attendance at The Grove in Watford.
Boris Johnson said Britain is "rock solid" in its commitment to Nato as he addressed leaders.
In opening remarks at the start of a meeting of the North Atlantic Council, the Prime Minister said: "I'm delighted to welcome everybody here to the United Kingdom to celebrate the 70th anniversary of Nato.
"I do feel that our alliance is coming home because Britain was a founding member of Nato and it was here that Nato opened its first headquarters, of course, in Belgrave Square, shortly actually before moving to Paris."
U.S. President Donald Trump arrives at The Grove hotel and resort in Watford, Hertfordshire. (AP Photo/Evan Vucci) (Image: Copyright 2019 The Associated Press. All rights reserved)
He went on: "70 years on, we are rock solid in our commitments to Nato and to the giant shield of solidarity that now protect 29 countries and nearly a billion people.
"The fact that we live in peace today demonstrates the power of the simple proposition at the heart of this alliance: that for as long as we stand together, no-one can hope to defeat us, and therefore no-one will start a war."
Mr Johnson continued: "History shows that peace cannot be taken for granted, and even as we celebrate this anniversary we must ensure that our deeds match our words.
"The atrocity in London last Friday shows why we must work together to combat terrorism and the vital importance of Nato's missions to counter this threat."
Armed police patrol the golf course at The Grove hotel in Watford, Hertfordshire, where Nato leaders are attending their annual summit. Steve Parsons/PA Wire
Photographers record the arrival of a motorcade at The Grove hotel in Watford, Hertfordshire, where Nato leaders are attending their annual summit. Stefan Rousseau/PA Wire
Prime Minister Boris Johnson arrives for the annual Nato heads of government summit at The Grove hotel in Watford. Chris J Ratcliffe/PA Wire
Staff clean the carpet ahead of the annual Nato heads of government summit at The Grove hotel in Watford. Chris J Ratcliffe/PA Wire
Nato leaders during the annual Nato heads of government summit at The Grove hotel in Watford. Steve Parsons/PA Wire
A general view of members during the annual Nato heads of government summit at The Grove hotel in Watford. Stefan Rousseau/PA Wire
Nato leaders pose for a photograph during the annual Nato heads of government summit at The Grove hotel in Watford. Steve Parsons/PA Wire
Security at The Grove hotel in Watford, Hertfordshire, ahead of the NATO leaders meeting this week. Steve Parsons/PA Wire
The Grove hotel in Watford, Hertfordshire, ahead of the NATO Leaders Meeting this week. Steve Parsons/PA Wire
Police outside The Grove hotel in Watford, Hertfordshire, ahead of the NATO Leaders Meeting this week. Steve Parsons/PA Wire
Police outside The Grove hotel in Watford, Hertfordshire, ahead of the NATO Leaders Meeting this week. Steve Parsons/PA Wire
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