The European Commission started an investigation into whether the safeguard measure currently in place on imports of certain steel products should be prolonged beyond the end of June.

The investigation was initiated following the request of 12 EU member nations, the commission said in a statement on Friday.

The measures involve a 25% tariff on EU imports of 26 types of steel ranging from stainless hot-rolled and cold-rolled sheets to rebars and railway material when the shipments exceed a three-year average.

Under World Trade Organization rules, safeguard measures are normally supposed to be limited in time and gradually loosened. The current steel curbs are due to lapse in mid-2021 and the overall quotas are being increased by 3% over the remaining period.

The investigation will be concluded by the end of June when the measures are due to expire, the commission said.