Vladimir Putin has used his annual Victory Day speech in Moscow's Red Square to justify his war in Ukraine and denounce Nato.

Speaking in front of hundreds of military personnel and flanked by a few world leaders, the Russian president said he was fighting a "just" war and called Ukraine an "aggressive force" that is being "armed and supported by the whole bloc of Nato".

His remarks come amid muted celebrations across parts of Russia to mark the nation's biggest national holiday, which commemorates the Soviet Union's victory over Nazi Germany.

Ahead of the celebrations, Russia and Ukraine agreed to observe a three-day ceasefire, which was announced by US President Donald Trump on Friday.

Following the parade, Russia's defence ministry accused Ukraine of breaking the ceasefire, without providing details. Ukraine did not immediately comment.

For the first time in years, no armoured vehicles or ballistic missiles featured in Moscow's Victory Day parade.

But under tightened security, military personnel marched in droves across Red Square.

Addressing the crowd, Putin started his speech by commemorating the sacrifices of USSR soldiers during World War Two.

"The great feat of the generation of victors inspires the soldiers carrying out the goals of the special military operation today," he said, referring to the war in Ukraine.

"They are confronting an aggressive force armed and supported by the whole bloc of Nato. And despite this, our heroes move forward."

The Russian leader went on to celebrate the citizens of Russia, making reference to the contributions of workers to its war effort, including scientists, inventors, military correspondents, doctors and teachers.

"No matter how military tactics change, the future of the country is being provided for by the people," he said.

Immediately after the speech, cannons fired successive rounds before music was played by a military brass band.

Foreign guests in attendance included Belarus's leader Alexander Lukashenko, Malaysia's King Sultan Ibrahim and Uzbekistan's President Shavkat Mirziyoyev.

Slovak Prime Minister Robert Fico, the only representative of the EU to attend, was also pictured meeting Putin at the Kremlin ahead of the parade.

Markedly fewer world leaders turned up compared to last year's 80th anniversary parade, which featured 27 leaders including China's President Xi Jinping and Brazil's Luiz InΓ‘cio Lula da Silva.

Russian TV viewers were shown a broadcast of soldiers on the front lines after Putin's speech.

Following the ceremony in Red Square, Putin laid flowers at the Tomb of the Unknown Soldier before attending a reception at the Kremlin.

Victory Day celebrations took place in other parts of Russia, though in fewer numbers than previous years.

In far-eastern Vladivostok, a parade and an Immortal Regiment march honoured war veterans.

Marches also took place in a number of other cities including Krasnoyarsk, in Siberia, and St Petersburg, state media reported.

Other parades were called off altogether.

Some virtual events were scheduled to take place instead, though internet outages were expected to disrupt them.

Under Putin, Victory Day has been used a propaganda tool to show off Russia's military might.

But it is also seen as a moment to remember the sacrifices made in World War Two - or the Great Patriotic War as it is called in Russia - in which 27 million Soviet citizens died.

Russia's full-scale invasion of Ukraine was launched in 2022 and has been going on for more than four years.

Despite the movement of troops and military equipment to the front lines, Russia had continued to feature military hardware such as tanks, missiles and other weapons in its annual Moscow parade up until now.

But last week officials announced this year's parade would be scaled back, citing the "current operational situation".

"Our tanks are busy right now," Russian MP Yevgeny Popov told the BBC earlier this week. "They are fighting. We need them more on the battlefield than on Red Square."

Security measures have also been tightened, with threats of Ukrainian drones used to justify the paring back of this year's parade.

A three-day ceasefire between Russia and Ukraine appeared to hold as the parade took place in Moscow.

But afterwards, Russia's defence ministry claimed Ukraine had violated the truce. It added that Russia would continue to observe the ceasefire.

Earlier in the week, Putin had announced a ceasefire for 8-9 May, while Kyiv had called for an indefinite truce, starting 6 May.

Since those announcements, the two countries have accused each other of extensive battlefield ceasefire violations.

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