The damage, which authorities have said was discovered on Sunday, directly targeted "the security of the Polish state and its civilians," Tusk wrote on X.

The explosion was on the rail link running from Warsaw to the Polish city of Lublin and connects to a line serving Ukraine.

"This route is also crucially important for delivering aid to Ukraine," he added after visiting the site of the incident in Mika, 100 kilometres (62 miles) southeast of Warsaw.

According to Tusk, the damage "was likely intended to derail a train". An incident was avoided as a train driver alerted specialized services to "anomalies in the railway infrastructure" before stopping the train.

No one was injured in the incident. Tusk also reported another incident that occurred on the same line, where windows in one carriage were shattered, most likely due to a damaged rail.

An investigation was immediately launched by the police and special services. "We will catch the perpetrators, no matter who their sponsor is," said the Prime Minister.

Since the beginning of Russia's invasion of Ukraine in February 2022, Poland, a member of NATO and the EU, claims to have been the target of sabotage attempts allegedly orchestrated by Russia.