Pakistan, Oct. 6 -- PARIS - France was thrown into deeper political turmoil on Monday after its newly appointed Prime Minister Sebastien Lecornu resigned only hours after announcing his cabinet, amid growing threats from both allies and opposition to topple his fledgling government.

Lecornu's abrupt resignation - both unexpected and unprecedented - sent shockwaves through France's political landscape, as well as its financial markets. French stocks tumbled and the euro weakened following the announcement, reflecting fears of prolonged instability in Europe's second-largest economy.

After weeks of cross-party consultations, Lecornu, a close ally of President Emmanuel Macron, had only just named his new ministers on Sunday. The first cabi...