Germany's helping hand for Greece costs Germans a tax cut and may cost Chancellor Angela Merkel her office

(Angela Merkel's)  conservative-liberal coalition was trounced in key regional elections on Sunday amid rising anger over the deal that will cost her country £19 billion.

The result stripped her government of its majority in the country's Bundesrat, or senate, and her ability to pass reforms cutting public spending.

Senior figures within her Christian Democrat Party (CDU) said they had lost confidence in her ability to guide the country and called for her to go.

Germany's Der Spiegel magazine said that up to 10 regional Christian Democrat leaders had begun plotting to remove her after her Greece policy "failed its first democratic test."

Willy Wimmer, a veteran CDU politician and a former minister, called for her "immediate resignation". Meanwhile, Josef Schlarmann, a regional leader of her centre-right CDU party, accused Mrs Merkel of having a "strategy of doing nothing" to tackle economic reform and doing too little resist the Greek bail-out.

The election defeat means the German Chancellor has lost control of the legislative process, allowing Social Democrats and Greens to block reforms aimed at cutting Germany's high public spending.

Juergen Ruettgers, the Christian Democrat leader in North Rhine-Westphalia, admitted: "Greece has dominated the last phase of the campaign as people felt uncertain and many had the feeling: 'Why do we have to help? And where does it end?'"

Yesterday (MON), Mrs Merkel was forced to admit her government would have to abandon planned tax cuts because of Germany's payout to Greece and a new commitment to help other struggling euro zone countries as part of an EU bail-out agreed in Brussels yesterday.

"We've suffered a stinging defeat, there's no way around it," she said. "Tax cuts won't be possible for the foreseeable future. We see that in the debate about the euro, about the guarantees and much else."

Germany's opposition Social Democrats yesterday vowed to use the chancellor's new weakness to disrupt her government's plans to reform health care and taxes.