WASHINGTON/LONDON (Reuters) -From punishing Brazil to trying to curb imports of fentanyl, U.S. President Donald Trump has wielded the threat of tariffs as an all-purpose foreign policy weapon. With a Friday deadline for Russia to agree to peace in Ukraine or have its oil customers face secondary tariffs,

India, which now faces among the highest tariff rates imposed by the US, called the levy "unjustified and unreasonable".

Tariffs on Indian exports to the United States will surge to 50 percent by late August, as part of an effort by President Trump to pressure Russia into resolving its war in Ukraine.