Prince Rainier III (search) of Monaco is conscious and his heart, lung and kidney functions have stabilized, the royal palace said Sunday, as worshippers in Monaco attended Easter Mass (search) with a special prayer for Europe's longest-serving ruler.

The medical update came a day after the palace issued the most pessimistic report yet on the 81-year-old monarch's prospects for survival. He remains on a respirator.

"The cardiac, lung and kidney functions that did not stop deteriorating have stabilized," the palace said in the new health bulletin, signed by three doctors.

Rainier "is conscious, but under sedation, which allows him to withstand respiratory assistance that is absolutely indispensable," it said.

The prince's prognosis remains "very reserved," the palace said — apparently a notch less severe than the "extremely reserved" judgment given by doctors Saturday. Rainier's health remains "worrisome," it said.

At Monaco Cathedral (search), where the prince married American actress Grace Kelly (search) in 1956, some worshippers sat in pews with copies of Monaco Matin newspaper before Mass began.

"Prince Rainier: The Worst Ever," read the front-page headline. Archbishop Bernard Barsi, who led the Mass, visited the hospital Saturday, the newspaper reported.

In his call to prayer, Barsi said the health of both Rainier and of Pope John Paul II "worries us greatly."

"May God support them in their ordeal. May they know that they can count on our prayers and our affection," he said.

Monaco's 32,000 people are overwhelmingly Roman Catholic. While a prayer for the prince is part of every Sunday Mass, this week's had special significance. A prayer written in Latin in the Mass program said: "God protect our Prince Rainier and answer our prayers in this time that we call on you."

As worshippers wished each other a happy Easter, many were relieved upon hearing that the prince's condition had improved.

"It's good news, really wonderful," Roger Durdilly said as he exited the cathedral. "He is like the pope. He wanted to stay in power until the end."

Rainier, who has suffered ill health in recent years, was hospitalized at the Cardio-Thoracic Center on March 7 with a chest infection. He was transferred to the intensive care unit Tuesday when his health took a sudden turn for the worse.

Rainier, who has ruled Monaco since 1949, is beloved in the tiny principality — smaller than New York's Central Park — that he transformed into a modern and elegant enclave for the rich.

His family, the Grimaldis, has ruled Monaco for more than 700 years. His son, Albert, 47, long groomed to take Rainier's mantle as monarch, would take the title His Serene Highness. Albert's sister, Princess Caroline, 48, would be next in line to the throne, followed by her eldest son, Andrea, now 20.

Princess Grace, who died in a 1982 car crash, is buried in the crypt of the 19th-century cathedral sitting on a hilltop overlooking the Mediterranean not far from the palace.