Snowden is a whistleblower who leaked documents showing the US National Security Agency is gathering information from individuals globally through internet and phone data.
Last week, in an interview with UK newspaper The Guardian, the 29-year-old former contract employee of the NSA said he worked earlier for the CIA with diplomatic cover in Geneva, where the US has a mission to the United Nations.
“We have known for a long time that the activities of foreign intelligence services have expanded in Switzerland,” Maurer, who doubles as Swiss minister of defence, told NZZ am Sonntag.
“In this particular case, however, much still sounds absurd,” Maurer told the Sunday newspaper.
“We’ll see what ultimately remains of it.”
Snowden, a computer systems expert, said that it was while he was in Geneva (from March 2007 until February 2009) that he first considered going public with what he knew about American intelligence gathering activities.
"Much of what I saw in Geneva really disillusioned me about how my government functions and what its impact is in the world," he told The Guardian.
"I realised that I was part of something that was doing far more harm than good," he added.
Snowden claimed there was an operation in which an agent made friends with a banker, got him drunk so he was stopped for driving while intoxicated, and then helped him escape legal action.
In exchange, the man allegedly spied on Swiss banks to garner data for US tax authorities on money stashed abroad by Americans.
Maurer told NZZ am Sonntag that if the Swiss attorney general finds the activities of recruiting spies in Geneva violate Swiss law, he believed the federal government would back prosecution by the AG.
The case would be “somewhat embarrassing” for the US but at the request of the Swiss government the Americans would have to respond, he indicated.
Last week, Swiss Foreign Affairs Minister Didier Burkhalter told SRF radio that the government had sought clarification from the US embassy in Bern about the information alleged by Snowden.
Burkhalter expressed surprise about the American’s allegations and said if they were confirmed they would amount to a breach of the Vienna Convention on diplomatic relations.
He underlined that the government would not take action until it had all the facts in the case.
Meanwhile, some members of the Swiss People’s Party (SVP) said they favoured Switzerland offering asylum to Snowden, who is the subject of a criminal investigation by the FBI and sought refuge in Hong Kong.
President Maurer, an SVP member, disagreed with the proposal, telling NZZ am Sonntag that the idea “was not thought through”.
Snowden, he said, has “broken the law of his country” and Switzerland should not be offering him asylum.