Ukraine’s ambassador to the United Kingdom was fired on Friday after the diplomat called out the “sarcasm” in a comment made by Volodymyr Zelensky during a row about London’s supply of weapons to Kyiv. The presidential order announcing Vadym Prystaiko’s departure gave no reason for his dismissal. But it comes a week after Britain’s Defense Secretary Ben Wallace suggested Ukraine should show more “gratitude” for the help it’s receiving from the U.K., adding: “We’re not Amazon.” “We can wake up in the morning and thank the minister,” Zelensky said in a seemingly sarcastic response. “Let him write to me and tell me how to thank him.” Prystaiko later told Sky News of Zelensky’s comment: “I don’t think that kind of sarcasm is healthy.” The Independent reported that “very strong” phone calls took place between Prystaiko and Kyiv in the wake of his criticism amid fears his words could be used in Russia as evidence of splits between Ukraine and its allies.