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CAIRO, March 6 (Reuters) - Army chief Field Marshal Abdel Fattah al-Sisi, who is expected to become Egypt's next president, said on Thursday the country's economic situation is grave.

"Sincerely speaking, our economic situation is very difficult," Sisi told a military convention.

Three years of political turmoil since the uprising that swept autocrat President Hosni Mubarak from power have taken a heavy toll on Egypt's economy, deterring foreign investment and tourism, two of its main sources of foreign currency.

Sisi, who ousted elected Islamist President Mohamed Mursi last year following mass protests against his rule and has since become a popular public figure in Egypt, is expected to announce soon that he will run for president in a poll later this year.

On Thursday, the powerful army leader appeared to be sending a signal he is determined to tackle Egypt's economic troubles.

"I can see Egypt's problems in front of my eyes like I am seeing you all now," said Sisi. "The country will not develop by talk but by hard work and insistence."

(Reporting by Yasmine Saleh and Michael Georgy; Editing by Catherine Evans)

((yasmine.saleh@thomsonreuters.com)(+202 2578 3290))

Keywords: EGYPT SISI/ECONOMY