Angela Merkel’s decision to raise pension payments for the next two years on Wednesday threatened to become a political hazard for the German chancellor as a ferocious debate erupted in her party about whether to increase benefits for retirees even further.

The government’s decision to double the scheduled increase in pension payments this year and next prompted Jürgen Rüttgers, the Christian Democratic state premier of North Rhine-Westphalia, to call last weekend for additional benefits for low-earners going into retirement.