BAGHDAD (AP) — Iraq’s embattled Prime Minister Nouri al-Maliki, in a surprise speech late Sunday, resisted calls for his resignation and accused the country’s new president of violating the constitution, plunging the government into a political crisis at a time it is battling advances by Islamic State militants.

Al-Maliki is seeking a third-term as prime minister, but the latest crisis has prompted even his closest allies to call for his resignation. A parliament session scheduled for Monday to discuss the election and who might lead the next Iraqi government was postponed until Aug. 19.