ATHENS, Greece - Greece is talking with international creditors about a second bailout package "roughly equal" to the first $157 billion rescue it accepted a year ago, the prime minister confirmed Sunday.

George Papandreou also blamed Greece's bloated and inefficient state sector for bringing the country to its knees and vowed to effect deep changes with a fall referendum on the constitution that would make it easier to get rid of inept officials or workers.

His proposals were a populist response to widespread popular anger at politicians as austerity measures cut deeply into disposable incomes. Riots erupted on the streets of Athens last week against a new round of spending cuts and tax hikes being demanded by the European Union and the International Monetary Fund.

"I ask for a vote of confidence because we are at a critical juncture ... the debt and deficits are national problems that have brought Greece into a state of dependence that may have protected us from bankruptcy, but which we need to get out of," Papandreou said, opening a three-day parliamentary debate that culminates Tuesday in a confidence vote.

He dismissed any calls to default on the country's massive debt, saying this would be "a catastrophe for households and banks alike" and made it clear he would not back off from efforts to reduce the debt.

Papandreou called for an autumn referendum on changes to the political system, including to the country's constitution. He said he will appoint an independent commission of up to 25 people to collect proposals from citizens and submit a report before the fall vote.

Papandreou said the constitutional revision will make it easier to prosecute delinquent government officials, now protected by a strict statute of limitations. He added other changes would include reducing the number of deputies, more transparent funding of political parties and candidates and a new electoral system, possibly even with term limits.

European donors and the IMF are demanding that Greece pass new austerity measures before they release the next $17 billion loan from the first rescue package.

Spooked by financial markets' reaction to Greece's political turmoil, Germany on Friday dropped its demand that the private sector be forced to share in the pain of a second Greek bailout. Papandreou also reshuffled his Cabinet and named a new finance minister, Evangelos Venizelos, who was in Luxembourg on Sunday at a EU finance ministers meeting.