If Yan Fei were an ordinary person or even another world's wealthiest man, the two countries would not have taken Yan Fei's warning seriously, because such a Yan Fei wouldn't possess substantial martial force. However, when they realized that Yan Fei had already caused massive losses to The United States of America and that The United States military could not do anything to harm him even after a short period, even failing to cause substantial damage to Yan Fei and Dream Island, the two countries backed down. If Yan Fei, who even The United States of America couldn't deal with, were to turn against them, wouldn't their fate be even more miserable than that of The United States of America?
Thus, after some hesitation, Britain and Israel each called the former President of The United States of America, announcing the termination of all previous cooperation with The United States military.