After Sen. Bernie Sanders announced he'd been invited to a major Vatican-sponsored forum on poverty – a high-profile "get," taking place just ahead of the New York Democratic primary – a top Vatican official in charge of the event has called him out for a breach of diplomatic protocol.

Margaret Archer, president of the Pontifical Academy of Social Sciences, blasted the Vermont senator for "monumental discourtesy," suggesting he wrangled a back-door invitation that kept her in the dark, according to Bloomberg Politics.



Though he's made poverty and economic inequality a centerpiece of his campaign, Sanders' participation threatens to inject politics into a solemn, largely academic gathering, Archer told Bloomberg. The senator, she added, wasn't on anyone's official guest list.

"Sanders made the first move, for the obvious reasons," Archer said. "I think in a sense he may be going for the Catholic vote but this is not the Catholic vote and he should remember that and act accordingly – not that he will."

Archer's account is "categorically untrue," Michael Briggs, a Sanders spokesman, told Bloomberg. "The invitation came to the senator from the Vatican."

Bishop Marcelo Sanchez Sorondo, the academy's chancellor, said he arranged for Sanders' invitation, although Bloomberg reports that the bishop "repeatedly declined to say who initiated the contact."

The public imbroglio over how Sanders was invited, and by whom, forced his campaign to defend itself on a day when it should have been hailing a development that could benefit him on several levels. A trip to Rome helps Sanders upgrade his thin diplomatic experience, has the potential for a photo op that will appeal to New York Catholics and energize secular admirers of Pope Francis, who has a parallel message on the evils of greed and poverty.

Sanders himself on Friday trumpeted the invitation, saying he was "very excited" to have received it.

