
The German President has begged Poland for forgiveness at the start of memorial ceremonies to mark 80 years since the outbreak of the Second World War.

Speaking in the country's native language at a poignant service in Wielun, Poland, where the first Nazi bombs fell, he told the nation that Germans 'committed a great crime against humanity in Poland' and 'I bow my head before the Polish victims of Germany's tyranny'.

The sombre statement came as world leaders, including US vice president Mike Pence and German chancellor Angela Merkel, along with delegations from up to 40 other countries, to mark the beginning of a war that would cost the lives of tens of millions of people.

At dawn this morning, following the remembrance service in Wielun, London mayor Sadiq Khan joined officials at a ceremony near the Westerplatte memorial in Gdansk, Poland, where Polish and Nazi forces clashed for the first time during the Second World War. World leaders have gathered for an international ceremony in Warsaw and at the Pilsudski Square, named after 20th-century independence army leader Jozef Pilsudski.

Hundreds also massed in Berlin cathedral for a service to mark the beginning of the war.

When German tanks rolled across the border on September 1 1939 it marked the start of a bloody occupation that would cost the lives of six million Poles and countless Jews, which would then be followed by communist rule supported by the Soviets before the iron curtain began to unravel in 1989.

Notable absences at the anniversary observances include Vladimir Putin, who was not invited, Donald Trump, who cancelled his trip at the last minute due to a hurricane, and UK Prime Minister Boris Johnson.

German President Frank-Walter Steinmeier has begged Poland for forgiveness on the 80th anniversary of the start of the Second World War while making a speech in Wielun, where the first German bombs fell on the country

World leaders have gathered across Poland today to commemorate the 80th anniversary of the outbreak of the Second World War. (Pictured: Ukraine's President Volodymyr Zelenskly shakes hand with US vice president Mike Pence. Both attended the sombre ceremony in Warsaw, Poland's capital)

German chancellor Angela Merkel has also arrived for a memorial ceremony in Warsaw to mark the 80th anniversary of the start of World War Two. She is pictured here walking through the square with Polish Prime Minister Mateusz Morawiecki

Crowds gather ahead of a memorial ceremony at the Pilsudski Square in Warsaw, Poland, which was attended by world leaders and dignitaries from NATO and EU countries

A crowd stands in the shade of a cross to keep cool ahead of the international ceremony to commemorate the outbreak of the Second World War in the Piluski Square in Poland

Crowds in Gdansk which have turned out for the celebrations marking the 80th anniversary of the start of the Second World War. They are standing in front of a sign that reads 'no more war'

Soldiers march past the Westerplatte monument in Gdansk, which marks the place where Nazi German and Polish forces first clashed during the Second World War

The burning fort of Warsaw, photographed on 17 September 1939, as the German's continued their invasion of the country

Hitler pictured with his generals as they watch Nazi soldiers parade through the streets of Warsaw, Poland, on October 5 1939, following the capture of the city

Speaking at the ceremony also attended by the Polish President Andrzej Duda, the German President said: 'I bow my head before the victims of the attack on Wielun. I bow my head before the Polish victims of Germany's tyranny. And I ask forgiveness.

'It is the Germans who committed a crime against humanity in Poland.

'Anyone who claims it is over, that the national-socialists' reign of terror over Europe is a marginal event in German history judges that for himself.'

Polish President Andrzej Duda also gave a speech in Wielun, where he denounced Nazi Germany's attack on Poland, calling it 'an act of barbarity' and 'a war crime'.

However, he also thanked the German President's words, saying: 'I am convinced that this ceremony will go down in the history of Polish-German friendship.'

US vice president Mike Pence has also been seen getting off a plane ahead of a sombre service that he will attend in Warsaw's Pilsudski Square, named after 20th-century independence army leader Jozef Piludski.

German chancellor Angela Merkel has been pictured arriving at the ceremony in Warsaw, which will also be attended by delegations from up to 40 other countries.

Polish war veterans pictured attending the ceremony marking the 80th anniversary of the start of the Second World War in Warsaw, Poland, today

Holocaust survivor Edward Mosberg was also pictured attending the memorial ceremony in Warsaw, Poland

A World War Two veteran pictured attending the ceremony marking the 80th anniversary of the outbreak of the war in Pilsudski Square, Warsaw, with his family

Veterans from the Second World War and officials pictured standing at a ceremony to commemorate 80 years since the start of the Second World War in Warsaw, Poland, today

When it rained during the ceremony, veterans were also seen bringing out their umbrellas. They gathered in Warsaw today for the 80th anniversary of the outbreak of the Second World War, when Germany invaded Poland

World leaders and officials pictured on the podium in front of Polish soldiers. Hungarian president Janos Ader and Slovenian president Borut Pahor were also in attendance at the ceremony in Warsaw

Poles raise miniature flags at the ceremony to commemorate the 80th anniversary of the outbreak of the Second World War

US vice president Mike Pence arriving at Okecie Airport this morning as he prepares to mark the 80th anniversary of the Second World War with delegations from up to 40 other countries in Poland's capital Warsaw. President Trump cancelled his visit at the last minute due to a hurricane

US vice president Mike Pence pictured with other world leaders at the 80th anniversary of the outbreak of the Second World War ceremony in Warsaw, Poland

US vice president Mike Pence and Ukrainian President Volodymyr Zelenskly during a bilateral meeting with other world leaders in Warsaw, Poland, after the ceremony. National Security Adviser to the US, John Bolton, was also at the meeting

French prime minister Edouard Philippe (second right) with Belgian prime minister Charles Michel (left) at a ceremony marking 80 days since the outbreak of the Second World War in Pilsudski Square, Warsaw, Poland

Polish President Andrzej Duda (centre right) with his wife Agata Kornhauser-Duda standing alongside German President Frank-Walter Steinmeier (centre left) and his wife Elke Buedenbender before commemorative ceremonies in Warsaw

German chancellor Angela Merkel with Polish Prime Minister Mateusz Morawiecki at the ceremony in Warsaw to commemorate the outbreak of the Second World War today

German President Frank-Walter Steinmeier (right) and Polish President Andrzej Duda (left) at a memorial in Westerplatte, Gdansk, today to mark the 80th anniversary of the Second World War

Polish President Andrzej Duda (right) and German President Frank-Walter Steinmeier (left) lay candles at a memorial in Westerplatte, Gdansk, to mark the 80th anniversary of the Second World War

London mayor Sadiq Khan standing next to the vice president of the European commission, Frans Timmermans (right, 3rd left) and the mayor of Gdansk Aleksandra Dulkiewicz (right, 4th left) at the ceremony in Gdansk this morning. Later in the day he was pictured speaking at a second ceremony (left)

Rabbi Dov Hejn (left) and chairman of the Jewish Community in Gdansk, Michal Samet, (right) attend a ceremony marking the 80th anniversary of the outbreak of the Second World War in Gdansk, Poland

London's mayor was also photographed standing shoulder to shoulder with the European commission vice president Frans Timmermans and the mayor of Gdansk Aleksandra Dulkiewicz.

In a statement, Sadiq Khan said he was there to 'bang the drum' for London and 'spread the message that, however Brexit turns out, the city will always be open for business, trade and talent and a welcoming home for Polish citizens'.

'With far-right extremism on the rise on a scale we have not seen for decades, I will also be using this visit to make the positive case for tolerance and inclusion in London, Poland and across Europe.'

Writing in The Observer today, Sadiq Khan has also slammed Boris Johnson and Donald Trump as 'extreme right-wing leaders' and claimed that the lessons of the Second World War are 'in danger of being forgotten'.

He also labelled the US president the 'global poster-boy for white nationalism' and accused him of being an inspiration for right-wing leaders around the world.

Supporters of President Donald Trump pictured hanging banners prior to the commemoration of the 80th anniversary of the Second World War in Warsaw, Poland

Donald Trump with his wife Melania and the Polish President Andrzej Duda with his wife Agata Kornhauser-Duda at the Krasinski Square in Warsaw during a visit to the country on July 6 2017

Thousands also gathered in Berlin cathedral to mark the 80th anniversary of the Second World War. The Luftwaffe attack on the small Polish town of Wielun was the first time bombs were dropped on the country

A priest walks up to the altar at the memorial service in Berlin this morning to mark the 80th anniversary of WWII

Polish prime minister Mateusz Morawiecki and Belgian prime minister Charles Michel (left) shake hands at the ceremony in Warsaw today. German first lady Elke Buedenbender (left), Polish first lady Agata Kornhauser-Duda (centre) and Karen Pence, wife of US vice president Mike Pence (right) pictured also attending the ceremony

UK prime minister Boris Johnson has also paid his respects to the 'bravery' of Poles during the Second World War.

Speaking in a video message filmed in 10 Downing Street, he said: 'On almost every front, Poles fought magnificently for the Allied cause.

'They served alongside the British Army storming the Nazi fortress at Monte Casino, vanquishing Rommel in North Africa and took off from British airports to defend British skies in 1940.'

'Britain has been proud to stand with Poland. Our friendship, born in the struggle against tyranny, is symbolised today by our unbreakable commitment to the NATO alliance.'

The memory of World War Two is a major issue in Poland, with the ruling Law and Justice party (PiS) using it to whip up nationalist feeling by claiming western countries have not recognised the extent of the country's suffering and bravery under Nazi occupation.

Writing in German newspaper Die Welt on Friday, two days before the ceremonies, prime minister Mateusz Morawiecki said: 'The experience of Poland in the Second World War greatly differed from western European countries. The occupation of France and Poland was incomparable.'

Articles in a similar vein are due to appear in newspapers across Europe and the United States this weekend, which are being funded by a foundation financed by state companies.

As part of its campaign, the Polish National Foundation also paid for supplements in some newspapers consisting of a copy of their front pages from Sept. 2, 1939, that highlighted the Nazi German army's attack on Poland.

It is also becoming a central campaign theme ahead of Poland's general election, due on October 13 this year, with the ruling PiS accusing other parties of failing to protect the country's image on the world stage.

In a move likely to increase tensions between Poland and Germany, fuelled under the PiS government, Morawiecki renewed calls for wartime reparations in recent days.

Beginning on September 1, 1939, the invasion of Poland by Nazi Germany saw Adolf Hitler's troops attack the country from the north, south, and west. Hitler had been originally set to invade the country in August but wavered when Britain signed the Polish-British Common Defence Pact, which committed it to defend Poland and guarantee its independence in the face of German aggression. Above: Adolf Hitler observes German troops crossing the Vistula River, near Chelmno, Northern Poland

The attack on Poland actually began when, in the early hours of September 1, the German battleship Schleswig-Holstein opened fire on the Polish military transit depot at Westerplatte, in what was then the Free City of Danzig and is now Gdansk. Above: Workshops at the port on fire after their attack by Nazi Germany

The devastating attacks on Warsaw led to the surrender of the Polish garrison on September 27 - they had endured 18 days of continuous bombing and finally surrendered at 2pm that afternoon. Above: The ruins of the Lubomirski Palace in central Warswaw

At 4:45am on September 1, 1939, around 1.5million German troops invaded Poland all along its 1,750-mile border with German-controlled territory. Above: A map drawn on parchment showing the directions of the German army's attack

Throughout September, Warsaw remained under siege, with the largest and most devastating air attacks coming on September 25 and 26. Hundreds of tons of high explosive and incendiary bombs were dropped on Warsaw. These were accompanied by heavy shelling from artillery. Three key forts in the city were captured, around 25,000 civilians were killed and large parts of the city were reduced to rubble. Above: The bombed Warsaw West railway station

The Polish army's defiant defence of Westerplatte, which saw them hold out for seven days, is still seen as a heroic symbol of resistance in the country. During the attack, Poles withstood numerous assaults, shelling from German warships and dive-bomber attacks from the skies

Despite Britain and France's declaration of war on Germany on September 3, they did not provide any military assistance to the country because they had been entirely unprepared for the rapidity of the Nazis' invasion. Above: A German propaganda photograph shows German soldiers dressed as Gdansk Police officers pretending to break the barrier at the border crossing between Poland the Free City of Gdansk

In August 1939, Germany had signed a non-aggression pact, known as the Nazi-Soviet pact, with the Soviet Union. In the agreement, the two countries agreed to divide Poland between them. Soviet forces were ordered into Poland on September 17. Above: A German soldier stands guard in Gdansk, Poland, on Septmber 1, 1939, with a sign which reads, 'Stop! Danger! Live ammunition being fired'

Behind Hitler's invasion of Poland was his desire to create 'Lebensraum', or 'living space' for German people. His theory of a racial hierarchy regarded Slavic people - the native population in Poland - as far inferior to 'Aryan' Germans. Above: German battleship SMS Schleslen bombards Polish artillery positions on September 27 on the Hel peninsula in northern Poland

Germany, one of Poland's biggest trade partners and a fellow member of the European Union and NATO, says all financial claims linked to World War Two have been settled.

The cancellation of Trump's visit is a disappointment to the PiS government, which is seen as one of Washington's closest allies in Europe. Polish and U.S. officials have said another visit could be scheduled in the near future.

Opinion polls show PiS is likely to win the October ballot. The party's ambition is to galvanise voters and disprove critics by winning a majority that would allow it to change the constitution.