Athens (AFP) - Capital controls imposed by the Greek government are taking a heavy toll on the country's businesses, a survey showed Monday, with nearly a quarter saying they are seeking to move their headquarters abroad.

Endeavour Greece, a non-profit group that supports entrepreneurs, found that 58 percent of the 300 companies it surveyed between July 13 and July 17 reported a "significant impact on their operations caused by the limitations imposed to cross-border transactions".

"Many of these companies cannot import raw material or have access to foreign services and infrastructure," the group said in a statement, adding that 23 percent "plan to transfer their headquarters abroad for security, cash flow and stability reasons".

More than two thirds of the companies -- 69 percent -- reported a "significant drop in turnover", with 11 percent forced to decrease or suspend production due to shortages of raw materials.

Greece imposed a raft of capital controls on July 29, closing the banks and restricting cash withdrawals in a bid to prevent a disastrous bank run from draining money out of the financial system.

Banks reopened on Monday and restrictions on cash withdrawals have been partially relaxed, though the capital controls remain in place.

Endeavour Greece reported that businesses were facing "significant impediments" due to the continuing ATM limits, but on "a smaller scale".

Nearly half of the companies -- 45 percent -- said they had been forced to postpone payments to suppliers.