Novichok Allegations: The joint statement comes as the United Nations Security Council meets to discuss the attack on former Russian spy Sergei Skripal and his daughter Yulia in March and its fallout.
Russia has continued to deny any involvement.
The UK has named two men believed to be from Russia’s military intelligence service, the GRU, as the main suspects.
Theresa May told the Commons that the suspects had entered the UK on Russian passports using the names Alexander Petrov and Ruslan Boshirov.
She told MPs the poisoning was “not a rogue operation” and was “almost certainly” approved at a senior level of the Russian state.
The statement from Mrs May, Emmanuel Macron, Angela Merkel, Donald Trump and Justin Trudeau said: “We, the leaders of France, Germany, the United States, Canada and the United Kingdom, reiterate our outrage at the use of a chemical nerve agent, known as Novichok, in Salisbury on March 4.”
The leaders welcomed progress in the investigation, but urged those with more information to go to UK authorities.