The US government has authorised limited crude oil exports to Europe for the first time in years, raising new questions about how companies are testing the limits of a controversial, decades-old exports ban.

The Department of Commerce has granted two licences to export US crude to the UK since last year and another two to Italy, according to data Reuters obtained through a Freedom of Information Act request.

One application for German exports was filed in January and is awaiting a decision by the Bureau of Industry and Security (BIS), which is responsible for reviewing requests to export crude under a 1975 law that bans most shipments with a few exceptions, including sales to Canada and re-export of foreign oil.

These are the first permits for shipments to the UK since at least 2000 and the first to any European country since 2008, according to data from the BIS.

The bureau has approved 120 licences since January 2013, nearly 90 per cent of which were for sales to Canada, the data show.

It was not immediately clear under which provisions BIS granted the European export licences. The current regulation allows foreign crude to be re-exported from the US if it is not commingled with US crude, an option that some Canadian producers are said to be using.

In rare cases, the regulation permits the exchange of US oil for foreign crude or refined products of higher value, which has become an attractive option with the growing surplus of light, sweet shale oil.

Whatever the case, the licences could add to the growing debate in Washington on the benefits and pitfalls of lifting the ban, among the year’s most urgent energy policy questions, as the relentless rise in shale oil production threatens to saturate domestic refiners as soon as this year.

With US oil production at a 25-year high, many oil producers are eyeing other markets and have called for an end to the ban on exports, which they consider a relic of the 1970s, when the Arab oil embargo led to steep prices at the pump.

If more exports to Europe are allowed, refiners across the Atlantic may have cause to celebrate since access to cheap, high-quality US shale oil would help revive their margins.

A handful of licences have also been regularly approved over the past decade for countries in central America or Asia, either for the export of heavy California crude or the re-export of foreign-origin oil, according to a BIS statement released last year.

But European countries have rarely appeared on the list. Two permit applications filed in 2011 for exports to Switzerland and one for exports to the Netherlands were not approved. The two approved UK permits were for shipments with a total maximum value of $1.8 billion, while those to Italy were valued at $3.12 billion. The application for German exports was worth $2.6 billion, the data show.