The US, UK and Australia have joined forces to develop hypersonic and anti-hypersonic weapons.
As war in Ukraine rages, the three members of the Aukus military pact reiterated their “unwavering commitment” to an international system which “respects human rights”.
Missiles that can fly at five times the speed of sound, (6,175 kilometres an hour) or more can outrun conventional missile defence systems.
UK Prime Minister Boris Johnson, US President Joe Biden, and Australian Prime Minister Scott Morrison issued a statement on Tuesday giving their reasons for the agreement.
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“In light of Russia's unprovoked, unjustified, and unlawful invasion of Ukraine, we reiterated our unwavering commitment to an international system that respects human rights, the rule of law, and the peaceful resolution of disputes free from coercion,” their statement said.
“We also committed today to commence trilateral co-operation on hypersonics and counter-hypersonics, and electronic warfare capabilities, as well as to expand information sharing and to deepen co-operation on defence innovation.
“These initiatives will add to our efforts to deepen co-operation on cyber capabilities, artificial intelligence, quantum technologies, and additional undersea capabilities.
“As our work progresses on these, and other critical defence and security capabilities, we will seek opportunities to engage allies and close partners.”
In the courtyard of their house, Vlad Tanyuk, 6, stands near the grave of his mother Ira Tanyuk, who died because of starvation and stress due to the war, on the outskirts of Kyiv. AP
A Ukrainian soldier walks with children passing destroyed cars due to the war against Russia, in Bucha, on the outskirts of Kyiv, Ukraine. AP
President Volodymyr Zelenskyy surveys the destruction in Bucha. AFP
Residential buildings damaged during fighting in the southern port city of Mariupol. Reuters
A bridge damaged by shelling in Bucha. EPA
A soldier stationed in Bucha, after the city was the recaptured by the Ukrainian army. EPA
Chervona Voloshin kisses Varvara Statenova goodbye as she heads home to Kyiv after being housed at a shelter for displaced people in Lviv, Ukraine. Getty Images
Parts of a destroyed aircraft at the Antonov airport in Hostomel, outskirts of Kyiv. AP
A Ukrainian territorial defence serviceman walks past a destroyed Russian armoured personnel carrier in the town of Borodianka, north-west of Kyiv. AFP
Tanya Nedashkivska recounts how her husband Vasyl Ivanovych, who served in Ukraine’s navy, was killed by Russian soldiers, in Bucha, Ukraine. He was arrested by Russian soldiers. Tanya looked for him for days and found him in a building's basement where two bodies were lying. She recognised him by his shoes and trousers. AP
Damaged residential buildings in the southern port city of Mariupol. Reuters
Families arrive to board a train at Kramatorsk central station as they flee the eastern city, in the Donbas region. AFP
Romanian politicians listen to President Zelenskyy’s speech by video link, on a screen in the parliament in Bucharest. AP
The remains of a Russian Su-35 aircraft that was hit by the Ukrainian armed forces in Kharkiv. Reuters
A damaged monument to Ukrainian poet Taras Shevchenko in the besieged city of Mariupol, southern Ukraine. Reuters
A man removes a door covering the opening to an underground concrete enclosure in which bodies of civilians killed by Russian forces, residents say, were dumped as people were unable to transport them to a cemetery in Bucha, Ukraine. AP
A Ukrainian soldier tries to convince a puppy to drink milk as residents wait for distribution of food products in Motyzhyn, Ukraine, which was until recently under the control of the Russian military. AP
The pain of war is evident as women wait for food aid in the village of Motyzhyn. AP
Ukraine's President Volodymyr Zelenskyy appears on screen during the 64th Grammy Awards at the MGM Grand Garden Arena in Las Vegas. AFP
The gutted interior of a theatre in central Mariupol, destroyed in the course of Ukraine-Russia conflict. Reuters
Desolation in Mariupol which has suffered intense bombardment. Reuters
A Ukrainian soldier walks in front of the remains of an Antonov An-225 Mriya cargo plane, the world's biggest aircraft, destroyed by Russian troops at an airfield in the city of Hostomel, in the Kyiv region. Reuters
A local woman salutes Ukrainian soldiers in the Chernihiv region. Reuters
A woman hugs a Ukrainian soldier after a convoy of military and aid vehicles arrived in the formerly Russian-occupied town of Bucha, near Kyiv. AP
Smoke rises after an attack by Russian forces in Odesa. AFP
Ukraine's President Volodymyr Zelenskyy presents an award to an injured Ukrainian service member at a military hospital in Kyiv. Reuters
A destroyed building in the eastern Ukrainian city of Kharkiv. AFP
People, mainly women and children, pass through the Medyka border crossing on their journey out of Ukraine and into Poland. Getty
Russia claimed its first use of the hypersonic Kinzhal, or Dagger, projectile, a weapon it said has a range of more than 2,000 kilometres.
The Kinzhal, which is launched from an aircraft, destroyed an arsenal at Delyatin in western Ukraine.
Kinzhal missiles can carry conventional or nuclear warheads and reach speeds of more than 3.2 kilometres a second, or 11,500 kph, Russian President Vladimir Putin said in 2018's state-of-the-nation address.
At that speed, the kinetic energy of the weapon could be enough to destroy a range of targets, even without a warhead.
The Aukus pact was signed last year and involved a deal for Australian nuclear submarines. This cut France out of an agreement to sell diesel vessels to the Australian navy.
The Aukus leaders said they were “pleased with the progress” Australia was making in the development of nuclear-powered submarines.