A Mexican bishop has proposed a "social pact" that would include drug traffickers to tackle violence that has prompted calls for a rethink of President Andres Manuel Lopez Obrador's security policy.

The pact was needed so that "all of society and even criminals could join in some way," Sigifredo Noriega, bishop of the violent northern state of Zacatecas, told the newspaper Milenio.

Questions about Lopez Obrador's security strategy have mounted since two Jesuit priests were murdered on June 27 in a church in the northern state of Chihuahua.

Mexican Catholic bishops urged the government after the attack "to review the security strategies that are failing."

On Monday the Mexican Episcopal Conference said it was committed to "dialogue to build a path of justice and reconciliation that leads us to peace."

People with missing relatives take part in a pre-Hispanic ritual during a protest against violence, in Mexico City on July 5, 2022
People with missing relatives take part in a pre-Hispanic ritual during a protest against violence, in Mexico City on July 5, 2022 AFP / Pedro PARDO

Lopez Obrador this week defended his security policy, which has focused on tackling the root causes of violence, including poverty.

He said Tuesday that while he supported forgiveness his government "does not negotiate" with criminals.

More than 340,000 people have been killed in a spiral of bloodshed since 2006 when the government of the time deployed the army to fight drug cartels.

The government blames most of the deaths on gangs involved in crimes including drug trafficking, fuel theft, kidnapping and extortion.