Six top members of Egypt's ruling party resigned Saturday in what appears to be the latest concession by the country's government to quell mass protests against President Hosni Mubarak.

But as pressure mounts on Mubarak's regime, the United States and key allies have faced a difficult foreign policy quandary: how to sustain a fledgling democratic movement without completely deposing Mubarak.

Meanwhile, the U.S. and leading nations in Europe seemed to edge closer to open support of Egyptian Vice President Omar Suleiman and a power-shifting plan. It's hoped that Suleiman will be able to achieve an orderly transition away from the decades-old rule of the Mubarak regime.

On Saturday, all six members of the Steering Committee of the General Secretariat -- the National Democratic Party's top decision-making body -- resigned and were replaced. They included the president's son Gamal Mubarak, as well as party secretary-general Safwat el-Sharif.

The younger Mubarak was thought to be in line to eventually succeed his father as president. But newly appointed vice president Suleiman had pledged that Gamal would not run for that post when elections are held in September.

There were mixed reports as to whether Hosni Mubarak had resigned as head of the National Democratic Party. But it appears he will continue in that role, which is separate from his post as president.

The outgoing members were considered among the party's most powerful leaders in the regime, and were unpopular among many Egyptians.

Despite the resignations, tens of thousands of anti-government protesters descended on Cairo's Tahrir Square on Saturday, for the 12th-straight day of mass demonstrations. They say they plan to continue holding anti-government rallies until Mubarak leaves office.

A new committee composed of various factions from the ranks of the protesters, including former presidential candidate Ayman Nour, has been formed to conduct negotiations on the protesters' behalf. But it says it will not enter transition talks until Mubarak steps down.

Youth activist Abdel-Rahman Youssef told The Associated Press that members of the group met with the prime minister late Friday to discuss how the standoff will end.

"The message is that they must recognize the legitimacy of the revolution and that president must leave one way or the other, either real or political departure," he said.

Youssef said "there is no force" that can dislodge young protesters from Tahrir square, which has become the heart of the demonstrations.

However, it remained far from clear whether their demands would be met.

In Germany, U.S. Secretary of State Hillary Rodham Clinton said the White House was endorsing Mubarak's vice president to handle the transition. Order was needed to keep extremists from seizing power, she said.

"It's important to support the transition process announced by the Egyptian government actually headed by now-Vice President Omar Suleiman," Clinton told the crowd at an international security summit in Munich.

Kamran Bokhari, a Middle East analyst with the global intelligence firm Stratfor, said the influence of the United States in Egypt can't be ignored.

The country of 80 million people has long been considered one of Washington's closest allies in the region -- it receives more than $1.5 billion a year in U.S. foreign aid -- and Bokhari said the White House is concerned about setting the right example.

"Clearly the United States would not like to humiliate President Mubarak -- that sets a very bad precedent for U.S. allies in the region," he told CTV News Channel.

News of the resignations in Mubarak's party came just hours after Egyptian Prime Minister Ahmed Shafiq appeared on state TV to tell viewers that stability is returning to the North African country.

Shafiq's statements suggested that Egypt's autocratic leader may stay on and try to ride out calls by the protesters for his immediate resignation.

The prime minister said that Friday's demonstration, which drew an estimated 100,000 protesters to Tahrir, or Freedom Square in downtown Cairo, had failed to oust the 82-year-old president.

"We haven't been affected and God willing next Friday we won't be affected," Shafiq said. "All this leads to stability."

A self-described "group of wise men" made up of the country's elite held talks with Shafiq regarding Mubarak's departure late Friday.

One proposal asked that the president hand authority to Suleiman. But Mubarak would retain his presidential title for the time being, allowing the country's ruler of three decades to save face as he's eased out.

Mubarak has refused to oblige requests for his departure, saying he plans to finish the remainder of his term through September. His aides have said the president should not be humiliated in the transition.

With files from The Associated Press