LISBON, March 1 (Xinhua) -- The head of the International Monetary Fund (IMF), Christine Lagarde, praised Portugal's economic recovery on Friday, but said the country needed to prepare for tougher times ahead.

"At the IMF we are very aware of the determination that has allowed Portugal to emerge from its economic crisis," said Lagarde, who was in Lisbon to attend a Council of State meeting as a special guest.

"Portugal and the Portuguese people deserve huge credit for their efforts, for which they should be proud," Lagarde said, in comments reported by the Lusa Portuguese News Agency.

But she sounded a note of caution in adding that "Portugal will have to take inspiration from its illustrious history, because the waters of the global economy are probably going to get a lot choppier."

"Risk levels are rising in the rest of the world and this will probably represent the main source of instability for the Portuguese economy," the managing director of the IMF said.

She recommended that Portugal "intensify its efforts to be prepared for the future", emphasizing the potential threat of disruption caused by technological change and by geopolitical events such as Brexit.

"A disordered Brexit will also affect Portugal," she said, "for it might prove a significant drawback to trade relations and tourism."

More generally, she hailed Portugal's "impressive progress in cutting the budget deficit and reducing financing costs."

But she said "structural reforms to increase savings, investment and productivity are essential in order to boost living standards, help deleverage the economy and reduce its vulnerability."

The Council of State is an advisory body to the Portuguese president and comprises 20 members, including the president, the prime minister and three former presidents.

Since becoming Portugal's president in March 2016, Marcelo Rebelo de Sousa has made a habit of inviting high-profile guest speakers to council of state meetings.

Past guests have included Mario Draghi, the president of the European Central Bank (ECB), and Jean-Claude Juncker, the president of the European Commission.