The Kremlin is watching Helsinki closely after Finnish leaders said they intended to apply for NATO member status “without delay,” according to furious Russian officials. “Russia will be forced to take retaliatory steps of military-technical and other characteristics in order to counter the emerging threats to its national security,” the country’s foreign ministry said in a Thursday statement. Finland’s President Sauli Niinistö and Prime Minister Sanna Marin had made a joint call for membership in the Western military alliance earlier on Thursday, saying it would strengthen their country’s security. “We hope the national steps still needed to make this decision will be taken rapidly within the next few days,” Niinistö and Marin said in a statement. The Finnish president tweeted the same day that he had spoken to Ukrainian President Volodymyr Zelensky about Finland’s NATO plans. Zelensky “expressed his full support” for the move, Niinistö wrote. In a joint news conference with U.K. Prime Minister Boris Johnson on the subject of NATO membership earlier this week, Niinistö addressed Russia directly, according to the Associated Press. “You caused this,” he said. “Look in the mirror.”