BEIRUT, Sept 18 (Reuters)

A Lebanon-based consulting company hit by U.S. sanctions said on Friday it was surprised by the move and accused Washington of seeking to choke the battered Lebanese economy.

The United States imposed sanctions on Thursday on an official from Hezbollah, a movement backed by Iran and deemed a terrorist group by Washington, and two firms based in Lebanon, which is wrestling with an economic crisis.

The U.S. Treasury said those targeted had ties to the heavily armed and politically powerful Shi'ite Muslim group.

The measures build on sanctions the United States imposed this month on two former Lebanese government ministers, who it accused of enabling Hezbollah.

"The company is surprised that the American administration accused it of corruption and enriching some individuals at the expense of the Lebanese people," said Arch Consulting, one of the two firms blacklisted by the Treasury Department.

The statement blamed Washington's "policy of sanctions and blockade" for Lebanon's "deteriorating economic conditions".

Lebanon's economy is collapsing after the nation built up a mountain of debt following its 1975-1990 civil war. Its banks are paralysed, its currency has crashed and it has defaulted on its sovereign borrowing.

Adding to its problems, a huge port blast in August ripped through Beirut, killing nearly 200 people, injuring thousands of others and causing damage estimated at billions of dollars.

French President Emmanuel Macron called Lebanon's president on Friday to discuss the need to press on with efforts to form a new government, seeking to give new momentum to France's initiative to pull the country out of crisis.