Pope Francis has called for more regulation of financial markets and rejected suggestions that his criticisms of unbridled capitalism smack of Marxism.

"Markets and financial speculation cannot enjoy absolute autonomy," he said in an interview published in La Stampa newspaper on Sunday, calling for greater ethics in the economy and a better distribution of the earth's resources.

"We cannot wait any longer to resolve the structural causes of poverty in order to cure our society of an illness that can only lead to new crises," he said.

Conservative Catholics, particularly in the United States, have criticised some of his past pronouncements on the economy, with several openly calling him a Marxist. But the Argentine pope said he was just stating Church teachings.

"If I repeat some sermons by the first fathers of the Church in the second or third centuries about how the poor must be treated, some would accuse me of preaching a Marxist homily," he said. "The New Testament does not condemn wealth but the idolatry of wealth."

He has condemned huge salaries and bonuses, calling them symptoms of an economy based on greed and also said speculation in food commodities was undermining the global fight against poverty and hunger.

The interview is from a chapter of an Italian book called "Pope Francis: This Economy Kills," to be published this week.