The US military's top general met Egypt's ruling field marshal on Saturday amid a row between the allies over impending trials of American pro-democracy activists.

The meeting in Cairo had been "long planned," according to General Martin Dempsey's spokesman, but officials were hoping Dempsey would persuade Cairo to back off the planned trials.

Colonel Dave Lapan said the general discussed with Tantawi and his Egyptian counterpart Sami Enan "a wide range of issues related to the long-standing security relationship between our two countries, including the issue involving US NGOs."

But he said he would not "further describe the contents and nature of their private discussions," in a statement emailed to AFP.

Dempsey had planned to hold a round-table discussion with journalists after the meetings, but it was called off with no reason given to reporters.

Egyptian judicial officials have announced plans to put dozens of pro-democracy activists, including 19 Americans, on trial over alleged illegal funding to foreign aid groups.

The move has shaken the Egypt-US alliance that has anchored America's Middle East policy for a generation and helped keep the peace between Israel and its Arab neighbours.

Outraged at the charges, some senior US lawmakers have warned that Washington's aid to Egypt could be jeopardised if the prosecution goes ahead.

The United States currently provides about $1.3 billion a year in aid to Egypt, one of the biggest packages offered to any nation.

Egyptian judges on Wednesday accused domestic and foreign groups, including American ones, of illegally meddling in the country's politics.

Fayza Abul Naga, the international cooperation minister widely seen as the driving force behind the trials, said on Saturday she did "not believe that a side issue such as the issue of civil society groups could affect the future of ties between Egypt and America."

Abul Naga added, in comments published by the official MENA news agency, that the row would not impact a one-billion-dollar loan Egypt had requested from the World Bank.

World Bank chief Robert Zoellick said last week he expected "tensions" as Egypt requests aid from the international lender, which in turn would demand progress on governance and democracy.

"We will want... to make sure it's transparent, that it relates to some of the changes that people were calling for or a broader social accountability. And there'll be tensions with that," he said of the requested loan.