The correct answer is - tariff.
The tariffs are used when a country wants to protect its own products, but also when it wants to make an economic blow to some country. The imposing of the tariffs means that the products the are imported will be more expensive, thus giving an advantage to the domestic producers, but usually is not seen fondly by the general population as many products that are imported and they use regularly are not suitable for their budget anymore. Also, by one country imposing tariffs on other countries, it comes back as a boomerang, and the other countries are imposing tariffs as well, so the export is starting to have harder times.
