“In Panama, there is a law that sets out retaliation measures against countries that include Panama in 'grey lists',” Alvaro Aleman, the minister for the presidency, equivalent to the post of prime minister, told a news conference.

The measures can include blocking foreign investment or withholding public tenders.

Aleman said that “the government is going to have to analyze the situation and is inclined to take a series of steps that naturally could go towards adopting means of retaliation.”

The government of Panama and the country's vital financial services sector are panicking in the wake of the massive data leak from one of the country's law firms, Mossack Fonseca.

The revelations show how some of the world's wealthy set up offshore companies for their assets to hide them from scrutiny.

They fear the revelations being published in media around the world could scupper years of work to shed Panama's past reputation as a haven for money launderers and tax cheats.

In February this year, the country managed to get off an international 'grey list' of tax havens by passing some reforms that curbed to some extent the anonymity of offshore companies.

But after the so-called Panama Papers revelations, France's finance minister, Michel Sapin, on Tuesday told the French parliament that France will put Panama back on their blacklist.

“France has decided to put Panama back on the list of uncooperative countries,with all the consequences that will have for those who have transactions” with the central American state, Sapin told parliament.

Panama “wanted to have us believe that it could respect major international principles,” Sapin said. “That's how it managed to avoid being on the blacklist of tax havens.”

France removed Panama from the list of Uncooperative States and Territories (ETNC) in 2012 after the two countries reached a bilateral accord on fighting tax evasion.

Panama's deputy foreign minister, Luis Miguel Hincapie, told the same media conference that the French ambassador to Panama would be summoned on Wednesday to explain France's move.

Foreign Minister Isabel De Saint Malo was also going to speak with her French counterpart Jean-Marc Ayrault.

“Panama must categorically reject any inclusion of Panama in a list and we will take steps if that happens,” Hincapie warned.