US President Donald Trump warned Wednesday that more punishment was coming for countries buying Russian energy products after slapping a 25% tariff on India that is supposed to go into effect Thursday.

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.