Tillerson posed the question at a meeting of foreign ministers from the Group of Seven (G7) industrialised nations on Tuesday, Censor.NET reports citing Reuters.
The new U.S. administration under President Donald Trump has indicated it might be less engaged on the international stage than some of its predecessors, telling its allies that it would put U.S. interests first.
Tillerson asked his European counterparts why American voters should care about the conflict in Ukraine.
Ayrault told reporters he had replied: "It is in the interests of the U.S. taxpayers to have a Europe that is secure and is strong politically and economically... You don't want a weak Europe, broken into bits and feeble.
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