ROME - Italian Foreign Minister Franco Frattini said on Tuesday Switzerland had misused the Schengen agreement and taken its members "hostage" by slapping a ban on Libyan officials which prompted retaliation by Tripoli.

Officials said on Monday that Libya had stopped issuing entry visas to the 25 European nations covered by Schengen -- some of which are not in the European Union, such as Switzerland -- in response to a Swiss entry ban on 188 of its citizens, including Libyan leader Muammar Qaddafi and his family.

"The Swiss government has put them on the Schengen blacklist. But this is not the Schengen agreement that we know," Frattini said in an interview published in La Stampa newspaper. "By acting in this way, Switzerland has taken hostage the other countries of the Schengen zone."

Libya has for months been locked in a row with Switzerland over the brief 2008 arrest of one of Qaddafi's sons in Geneva, and the subsequent prosecution in Libya of two Swiss citizens.

Frattini said Italy, whose Prime Minister Silvio Berlusconi has forged closer ties with Qaddafi, had asked Tripoli to reconsider its decision. But he said Schengen was supposed to be used to protect its member states from criminals and terrorists.

"It is not right that Schengen should be twisted by Switzerland into a means of exerting pressure: there are other ways of resolving the bilateral problem with Libya," he said.

"The (Swiss) Confederation's action, equating Qaddafi and other Libyan officials with international terrorists, perhaps could have been avoided."

The Swiss Foreign Ministry declined on Tuesday to respond directly to Frattini's comments but said Switzerland had been implementing a "restrictive visa policy ... since fall 2009 after two Swiss citizens were kidnapped and kept in custody in an unknown place for 52 days."

Swiss officials have said that other states in the Schengen zone have backed Switzerland's line on issuing visas to Libyans.

Italy in recent months has experienced its own frictions with the neighboring Alpine country, prompted by an Italian tax amnesty for citizens holding undeclared money illegally abroad.

Rome placed Switzerland on a blacklist of countries not cooperating with the amnesty, amid a global crackdown on banking secrecy. Italian tax inspectors raided dozens of Swiss banks in Italy, prompting Switzerland to summon Italy's ambassador in October.

The visa suspension left Europeans stranded at the airport in Libya and forced many to return home. The Libyan government gave no official confirmation or explanation of the measure.

Oil exporter Libya has been attracting growing foreign investment since it emerged from decades of international isolation and the visa move could harm its business reputation, though one analyst said the suspension would be short-lived.

-- with input from agencies