By Andrea Shalal

WASHINGTON (Reuters) -Sweeping tariffs announced on Wednesday by U.S. President Donald Trump pose a significant risk to the global economy at a time when growth has been sluggish, the head of the International Monetary Fund said in a statement on Thursday.

IMF Managing Director Kristalina Georgieva said it was important to avoid steps that could further harm the global economy and appealed to the United States and its trading partners to work constructively to reduce tensions.

"We are still assessing the macroeconomic implications of the announced tariff measures, but they clearly represent a significant risk to the global outlook at a time of sluggish growth," Georgieva said in her strongest comments to date on the risks posed by the U.S. trade actions.

"It is important to avoid steps that could further harm the world economy. We appeal to the United States and its trading partners to work constructively to resolve trade tensions and reduce uncertainty."

Georgieva said the IMF would provide its assessment of the announced tariffs when it releases an update to its World Economic Outlook during the April 21-26 meetings in Washington, D.C., that bring together members and shareholders of the IMF and the World Bank.

The head of the global lender on Monday told Reuters that Trump's push for wide-ranging tariffs was creating great uncertainty and denting confidence, but it was not likely to trigger a near-term recession.

At the time, Georgieva said the IMF would likely lower the economic outlook slightly, adding "we don't see recession on the horizon."

The U.S. tariffs announced on Wednesday went far beyond the levels that had been predicted or expected by trade experts.