Trade between Russia and Britain falls to its lowest level on record.

For the first time since records began, Britain had a month in which it imported no fuel from Russia, as trade between the two countries plummeted following Russia’s invasion of Ukraine, according to British government statistics released on Wednesday.

In addition to a sharp decline in imports of Russian fuel in June, imports of other Russian goods also fell that month to the lowest level since Britain’s Office for National Statistics began recording the data in 1997. Imports decreased to 33 million pounds ($39 million), or 97 percent less than the average monthly imports in the year to February, the month when Russia invaded Ukraine.

The figures show the extent to which the British government’s economic sanctions against Russia, which came into force in March, are having an effect. Self-sanctioning, where companies voluntarily seek alternatives to Russian goods, was also likely a factor in the steep decline in trade, according to the Office for National Statistics.

Exports of most commodities to Russia from Britain also dropped significantly, led by a decline in exports of machinery and transport equipment. The exception was medicine and pharmaceutical products, which increased by 62 percent from the prewar average. These products are exempt from sanctions.

Under sanctions, British companies have until the end of the year to end imports of Russian oil and coal and have been encouraged to find alternative sources until then. To make up for the decreased volumes of refined oil from Russia, British companies in recent months have increased imports from Saudi Arabia, the Netherlands, Belgium and Kuwait.

Before Russia’s invasion of Ukraine, Britain imported nearly a quarter of its refined oil from Russia, 6 percent of its crude oil imports and 5 percent of its gas imports. (Britain gets about half of its total crude oil imports from Norway.)

The European Union has also reduced its purchases of Russian gas ahead of a ban on the vast majority of the bloc’s imports of Russian oil, which will come into force at the end of the year. The E.U. also agreed to curb natural gas consumption from Russia. In the final week of June, total E.U. gas imports from Russia were down 65 percent from a year earlier, according to a report by the European Central Bank.

Russia is feeling the effect of sanctions. Its economy contracted sharply in the second quarter, declining 4 percent from a year earlier. Sanctions on Russia have led many American and European companies to exit the country and have cut off Russia from about half of its $600 billion reserves of foreign currency and gold.

One boost for Russia’s economy has been higher oil prices, which have helped it make up for revenue that would have come from buyers in Europe. India, China and Turkey have stepped up their purchases of Russian crude, providing temporary relief, but once the European Union oil ban comes into full effect, Russia will need to find buyers for roughly 2.3 million barrels of crude and oil products a day, about 20 percent of its average output in 2022, according to the International Energy Agency.