The Czech Republic released about 1.5 million barrels of crude from its emergency stocks, or 10 days of the country's average refining throughput, the IEA said on Wednesday.

Although Hungary announced on April 30 that it would make 3 million barrels of crude stocks available, not all of this has been taken up, the Paris-based IEA said in a report.

No stock release has been reported for Slovakia.

"We assume a total of 100,000 bpd impact on refinery throughput in these three countries over May-June, but expect operations to ramp up from July, even if this implies further crude stock draws," the agency said.

Crude oil stocks in the three countries were at 27 million barrels at the end of February, or around nine months of forward cover.

Poland released 5.9 million barrels of crude stocks, while Germany had not released any emergency stocks as of May 14, the IEA said.

In 2018, Poland received about 300,000 bpd through the pipeline for its Gdansk and Plock refineries, while Germany's Leuna and Schwedt refineries received 440,000 bpd.