WASHINGTON (AFP) - Seven days after the Egyptian military deposed the democratically elected president Mohamed Mursi, the United States has still not decided whether to call his ouster a "coup."

But top US officials on Wednesday, while continuing to insist the United States was not taking sides in Egypt's political upheaval, sought to untangle the convoluted position taken by the Obama administration.

"It's clear that the Egyptian people have spoken," said State Department spokesman Jen Psaki, when asked whether Washington still considered Mr Mursi the legitimate president.

"There's an interim government in place... this is leading the path to democracy, we are hopeful. And we are in touch with a range of actors. But obviously, he is no longer in his acting position." Challenged about the fact that, before his ouster, Egypt already had a democratically elected government, Mr Psaki replied: "It wasn't a democratic rule. That's the whole point."

While the United States had endorsed the Islamist leader's election last year as "free and fair," the administration of President Barack Obama had found him a mercurial partner and had long been uneasy about his failure to introduce a pluralistic government.

Nevertheless, millions of Egyptians came to believe the US administration was in fact trying to shore up an Islamist leadership.

Such charges might only be heightened if the US denounces the military's actions as a coup, while also paving the way to a freezing of some vital US$1.5 billion (S$1.9 billion) in US aid.

So US officials are engaged in verbal acrobatics, insisting Washington's role is to help ensure the country returns to a democratically elected civilian government, without passing judgement yet on last week's events.

"We remain deeply concerned about the removal of President Mursi from power," White House spokesman Jay Carney said.

But he stressed there were "consequences" about how they "designate the events that happen in Egypt." Ms Psaki highlighted that some 22 million people had signed a petition calling for Mr Mursi's removal. That "is a large number of people to voice their concerns about the method of governing," she said.

The ousted leader has not been seen in public since the Egyptian military arrested him on July 3. Egyptian officials say he is in a "safe place," but has not been charged.

Mr Psaki said his case had been raised by US officials in contacts with interim Egyptian leaders, but she refused to say whether Washington was calling for his release.

"The United States has conveyed strongly and clearly to the Egyptian military that the treatment of anyone who is arbitrarily arrested - whether it's President Mursi or other members of the Muslim Brotherhood - is important to the United States," Mr Psaki said.

"And we believe that the interim government must follow due process and, of course, respect the rule of law." She also defended US ambassador to Egypt, Anne Patterson, who has been the focus of some protestors' anger, accusing her of interfering in the country's politics.

"We firmly reject any claim, in the Egyptian press or otherwise... that we have been supporting certain sides," Ms Psaki reiterated.

There was so much "political polarisation" that "various political actors... are attempting to cloud the issues on the ground by making false claims instead of addressing the difficult issues Egypt currently faces."

Mr Carney added that the situation in Egypt was "complex," "difficult" and "challenging" but said the country must return to an elected civilian government.

"The alternative is chaos. The alternative is a failure of Egypt to reach its potential, its enormous potential," he said.