The best photos from the queen's NATO anniversary palace reception for world leaders

Queen Elizabeth II hosted a reception at Buckingham Palace in London on Dec. 3, 2019, for world leaders in town to mark the 70th anniversary of the NATO alliance. See the best photos from the event — as well as pictures from President Donald Trump and first lady Melania Trump's tea meeting with Prince Charles and Duchess Camilla — starting with this pic of the monarch, her heir and his wife greeting the Trumps at the reception. Keep reading for more…

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First lady Melania Trump, President Donald Trump, Prince Charles and Camilla, Duchess of Cornwall pose for photos before having tea at Clarence House in London on Dec. 3, 2019, ahead of the NATO Leaders Summit marking the 70th anniversary of the organization. How did NATO come to be? As Getty reports, France and the U.K. signed the Treaty of Dunkirk in 1947 in the aftermath of WW2 cementing a mutual alliance in the event of an attack by Germany or the Soviet Union. The Benelux countries joined the Treaty and in April 1949 expanded further to include North America and Canada followed by Portugal, Italy, Norway, Denmark and Iceland. This new military alliance became the North Atlantic Treaty Organisation (NATO). The organization grew with Greece and Turkey becoming members and a re-armed West Germany was permitted in 1955. This encouraged the creation of the Soviet-led Warsaw Pact delineating the two sides of the Cold War. 2019 year marks the 70th anniversary of NATO.

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Princess Anne watches as Queen Elizabeth II, Prince Charles and Duchess Camilla greet President Donald Trump and first lady Melania Trump during a reception at Buckingham Palace in London on Dec. 3, 2019, held as NATO leaders gathered to mark 70 years of the alliance.

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Duchess Kate greets guests at Buckingham Palace in London on Dec. 3, 2019, during a reception hosted by Queen Elizabeth II ahead of the NATO summit where leaders gathered to mark the alliance's 70th anniversary.

Queen Elizabeth II walks with President Donald Trump at a reception for NATO leaders hosted by the monarch at Buckingham Palace in London on Dec. 3, 2019, held as the group's members gathered to mark 70 years of the alliance.

President Donald Trump and first lady Melania Trump arrive at Clarence House in London to meet with Britain's Prince Charles and Camilla, Duchess of Cornwall on Dec. 3, 2019, ahead of the NATO alliance summit.

Duchess Kate greets guests at Buckingham Palace in London on Dec. 3, 2019, during a reception hosted by Queen Elizabeth II ahead of the NATO alliance summit.

Prince Charles looks on as Queen Elizabeth II meets Prime Minister of Canada Justin Trudeau at Buckingham Palace in London on Dec. 3, 2019, during a reception hosted by the queen ahead of the NATO alliance summit.

Camilla, Duchess of Cornwall talks with Prime Minister of Canada Justin Trudeau at Buckingham Palace in London on Dec. 3, 2019, during a reception hosted by Britain's Queen Elizabeth II ahead of the NATO alliance summit.

Queen Elizabeth II, Prince Charles and Camilla, Duchess of Cornwall share a look during a reception at Buckingham Palace in London on Dec. 3, 2019, held as NATO leaders gathered to mark 70 years of the alliance.

Queen Elizabeth II smiles while speaking to a guest during a reception at Buckingham Palace in London on Dec. 3, 2019, held as NATO leaders gathered to mark 70 years of the alliance.

Princess Anne talks with German Chancellor Angela Merkel at London's Buckingham Palace on Dec. 3, 2019, during a reception hosted by Queen ELizabeth II ahead of the NATO 70th anniversary alliance summit.

Princess Anne talks to Prime Minister of Canada Justin Trudeau, Prime Minister of Britain Boris Johnson, President of France Emmanuel Macron and NATO Secretary General Jens Stoltenberg during a reception at Buckingham Palace in London on Dec. 3, 2019, held as NATO leaders gathered to mark 70 years of the alliance.

Princess Anne talks to Prime Minister of Canada Justin Trudeau and Prime Minister of Britain Boris Johnson during a reception at Buckingham Palace in London on Dec. 3, 2019, held as NATO leaders gathered to mark 70 years of the alliance.

World leaders pose for a group photo at a reception for NATO leaders hosted by Queen Elizabeth II at Buckingham Palace in London on Dec. 3, 2019, to mark 70 years of the NATO alliance: (Back row, from left) Xavier Bettel, Prime Minister of Luxembourg; Egils Levits, President of Latvia; Gitanas Nauseda, President of Lithuania; Dusko Markovic, Prime Minister of Montenegro; Erna Solberg, Prime Minister of Norway; Mark Rutte, Prime Minister of Netherlands; Zuzana Caputova, President of Slovakia; Andrzej Duda, President of Poland; Antonio Costa, Prime Minister of Portugal; Klaus Iohannis, President of Romania; Marjan Sarec, Prime Minister of Slovenia, (middle row from left) Edi Rama, Prime Minister of Albania; Zoran Zaev, Prime Minister of North Macedonia; Mette Frederiksen, Prime Minister of Denmark; Juri Ratas, Prime Minister of Estonia; Emmanuel Macron, President of France; Angela Merkel, President of Germany; Kyriakos Mitsotakis, Prime Minister of Greece; Viktor Orban, Prime Minister of Hungary; Katrin Jakobsdottir, Prime Minister of Iceland; Giuseppe Conte, Prime Minister of Italy; Andrej Plenkovic, Prime Minister of Croatia, (seated from left) Sophie Wilmas, Prime Minister of Belgium; Rumen Radev, President of Bulgaria; Donald Trump, President of United States; Prince Charles, Prince of Wales; Jens Stoltenberg, Nato Secretary General; Queen Elizabeth II; Boris Johnson, Prime Minister of the United Kingdom; Justin Trudeau, Prime Minister of Canada; Pedro Sanchez, Acting Prime Minister of Spain; Recep Tayyip Erdogan, President of Turkey; Milos Zeman, President of the Czech Republic.

Prince Charles, NATO Secretary General Jens Stoltenberg, Prime Minister of Britain Boris Johnson, Prime Minister of Canada Justin Trudeau and more join other NATO leaders and Queen Elizabeth II for a group photograph at a reception hosted by the monarch at Buckingham Palace on Dec. 3, 2019.

Camilla, Duchess of Cornwall and Prince Charles greet President Donald Trump at Clarence House in London on Dec. 3, 2019, ahead of the NATO alliance summit.

Melania Trump and Camilla, Duchess of Cornwall exchange kisses as the first lady arrives for tea at Clarence House in London on Dec. 3, 2019, ahead of the NATO Leaders Summit marking the 70th anniversary of the organization.

First lady Melania Trump, President Donald Trump and Prince Charles, Prince of Wales pose for photos before having tea at Clarence House in London on Dec. 3, 2019, ahead of the NATO Leaders Summit marking the 70th anniversary of the organization.

First lady Melania Trump, President Donald Trump, Prince Charles and Camilla, Duchess of Cornwall pose for photos before having tea at Clarence House in London on Dec. 3, 2019, ahead of the NATO Leaders Summit marking the 70th anniversary of the organization.

Queen Elizabeth II talks with German Chancellor Angela Merkel at London's Buckingham Palace on Dec. 3, 2019, during a reception hosted by the monarch ahead of the NATO alliance summit.

Queen Elizabeth II chats with Canadian Prime Minister Justin Trudeau at a reception for NATO leaders at Buckingham Palace in London on Dec. 3, 2019.

Queen Elizabeth II walks with first lady Melania Trump in Buckingham Palace in London on Dec. 3, 2019, during a reception hosted by the monarch as NATO members gathered to mark 70 years of the alliance.

President Donald Trump and first lady Melania Trump arrive at a reception hosted by Queen Elizabeth II at Buckingham Palace in London on Dec. 3, 2019, for NATO leaders in town to mark 70 years of the NATO Alliance.