Poland will close Russia’s consulate in the northern city of Gdansk and announce a further response to an explosion on a key rail link to Kyiv within days, Foreign Minister Radoslaw Sikorski said.

Prime Minister Donald Tusk said the explosion and another attempted act of sabotage over the weekend were a major escalation by Moscow.

For all its modernization, Poland hasn’t lost its soul. The European Union sometimes calls Poland “defiant.” But to Poles, independence is sacred, as they know what it costs to lose it. The country protects its sovereignty with the instinct of one that understands the stakes.