"We have full confidence in the British assessment that the two suspects were officers from the Russian military intelligence service, also known as the GRU, and that this operation was nearly certainly approved at a senior government level", the statement issued by Canada, France, Germany, and the United States says.
In a statement that will deepen the diplomatic crisis between the two countries, the Prime Minister said: "The GRU is a highly-disciplined organisation with a well-established chain of command".
"This was not a rogue operation", Prime Minister Theresa May said of the two suspects believed to be part of the GRU, Russia's Main Intelligence Directorate.
US President Donald Trump, German Chancellor Angela Merkel, French President Emmanuel Macron and Canadian PM Justin Trudeau issued a joint statement with Mrs May agreeing with the British assessment that the operation was "almost certainly approved at a senior government level" in Moscow.
Kremlin chief Vladimir Putin bears ultimate responsibility for an nerve agent attack on a former Russian spy and his daughter in Salisbury earlier this year, Britain's security minister said on Thursday.
The two Russian nationals are believed to have been traveling under aliases, although they had genuine Russian passports with the identities of Alexander Petrov and Ruslan Boshirov.
Prosecutors can not apply to Russian Federation for the men to be extradited because Russian Federation does not have extradition agreements with the UK.
Detectives believe the front door of Mr Skripal's Salisbury home was contaminated with Novichok on March 4.
The suspects made two trips to Salisbury before flying back to Moscow from Heathrow Airport on the evening of March 4, hours after the Skripals were poisoned, police said.
Hours later, the men left the United Kingdom on a flight from Heathrow to Moscow - two days after they had arrived at Gatwick.
Neil Basu, head of UK Counter Terrorism policing, said the plot was "a remarkably sophisticated attack" which appeared to be a clear assassination attempt.
In the second incident, Dawn Sturgess, 44, and her partner Charlie Rowley, 45, were exposed to the same nerve agent used in Salisbury.
Police said they were liaising with prosecutors about further charges in connection with the death of Ms Sturgess and the poisoning of Mr Rowley.
Mr Basu said the manner in which the bottle and packaging was adapted makes it a "perfect cover" for smuggling the weapon into the country.
But "if they ever step out the Russian Federation, Britain and its allies will get them and we will bring them to prosecution", he added.
She also said "novichok" which was a military grade nerve agent was planted by the two who were officers in the GRU, Russian military intelligence.
"As we made clear in March, only Russian Federation had the technical means, operational experience and motive to carry out the attack". Britain has issued domestic and European arrest warrants for the suspects, meaning they can be detained if they leave Russian Federation for another European country.
The case, with its chilling cloak-and-dagger details, echoes the 2006 murder of Alexander Litvinenko, a former Russian agent who died after drinking tea laced with radioactive polonium-210 at a London hotel.
"For Scotland Yard, the point is as much as anything to prove that they can hunt down these individuals and work out who they are, identify them and publicly name them".
Russian Federation has denied any involvement in the attack using the nerve agent Novichok that left Skripal and his daughter unconscious on a park bench in Salisbury.
Sergei Skripal and his daughter were admitted to a hospital after being found unconscious on March 4 in Salisbury.
Inconspicuously labeled as "Nina Ricci Premier Jour" and bearing the words "Made in France", the bottle had been specially created to be leakproof and had a custom applicator, UK Metropolitan police said.
The events sparked a huge public health alert and plunged the UK Government's relations with the Kremlin into crisis.
Relations between Canada and Russian Federation have not been spared, with the two countries involved in various wars of words and tit-for-tat diplomatic expulsions - including one round in March that was in direct response to the Salisbury attack.
But late this weekend, it appears Florence will pass the first fork, and we will see if it gets captured by the blocking high. East Coast from Florence next week has increased, the Miami-based weather forecaster added.
Spotty to scattered showers will increase on Wednesday and Thursday as Tropical Storm Gordon's leftovers weaken well to our west. Rain and the flash flooding that can cause are the main threats expected from Gordon along with strong wind and storm surge.
Instead, the bank will reportedly focus on a custody product for digital currencies created to serve large, institutional clients. Major Cryptocurrency coins Ripple (XRP) is down by 11%, Bitcoin Cash (BCH) by 10.2% and EOS by 10.9% by the time of press.
He is a cult figure in China's internet industry and has attracted a big following among entrepreneurs and in pop culture. Alibaba started as a business-to-business marketplace, but had enormous growth when it started selling to consumers.
Maas said Germany was also concerned about massive bloodshed and "looming humanitarian catastrophe" inside Idlib. Just hours later, the UN Security Council will also meet at Washington's request, also to discuss Idlib.
Anastasija Sevastova , the 19-seed from Latvia, stunned Stephens with 6-2, 6-3 victories in straight sets. The Latvian had no apparent power or pace, but she had the touch and variety to smother Stephens' game.
Woodward told him that he made the request to at least a half-dozen people close to the president, and that it was never granted. Trump's election . "This is the worst job I've ever had", Woodward reports insiders saying of Kelly's remarks.
"I never go onto the pitch with the intention of injuring another professional so I have a very clear conscience", Ramos said. Spain got crashed out of the World Cup after being defeated in penalties against hosts Russian Federation .
Chris Collins were indicted in a matter of just two weeks - both politicians were two of Trump's earliest supporters in Congress. Mr Trump, who did not address the specifics of the charges, did not name the Republicans he was referring to on Twitter.
Time to restore sanity in U.S. politics: Barack Obama
Mr Trump, asked about that speech during a trip to North Dakota, quipped that he had watched it but had fallen asleep. But many Republicans saw the former president's re-entry on the campaign trail as a net positive for them.
Wildfire in Shasta County burns 15000
This dramatic time lapse of the #DeltaFire will show the smoke plume and pyrocumulus cloud during the day, and the fire at night. The Delta Fire was burning on both sides of Interstate 5, which has made it more hard to control the flames, Underhill said.
IPhone 9 may be priced higher than iPhone 8
Remember when Apple called the third-generation iPad the "new iPad", which would make zero sense when the next iPad came along? The "plus" models a bigger screen with a better camera and a multitude of more features in comparison to the lower models.
Denver Broncos: Earl Thomas doubtful to play on Sunday
He has sought certainty over his long-term future and used social media to make his case during the off-season. Thomas' absence from mandatory minicamp and training camp has subject him to roughly $1.6 million in fines.
Former Arizona US Sen. Jon Kyl to replace John McCain
This is why he accepted the position with the stipulation that he would not commit beyond the end of this congressional session. But Kyl, who was sworn in Wednesday, has only committed to serving through at least the end of this Congress.