Muslim men join in evening prayer 13 September 2001 at Mosque Foundation in Bridgeview, Illinois, a suburb of Chicago.

WASHINGTON, Sept 14 (AFP) - Americans heeded President George W. Bush's call to "a national day of prayers and remembrance," Friday, with services planned throughout the day across the country.

Under a steady rain, official Washington mourned at an inter-faith, invitation-only service at the Washington National Cathedral. The president, much of his cabinet, current and former lawmakers, and almost the entire diplomatic corps attended the midday service.

Former presidents Bill Clinton, George Bush, Jimmy Carter and Gerald Ford also attended, as did former Vice President Al Gore.

Vice President Dick Cheney was to attend a special memorial at the presidential retreat Camp David in Maryland, where he was moved Thursday to keep the president and vice president a safe distance apart.

At the cathedral, prayers and readings were offered by Christian, Muslim and Jewish leaders and Bush spoke of "our nation's sorrow" as the country endures "the middle hour of our grief."

"God's signs are not always the ones we look for. His purposes are not always our own," Bush said. "We ask Almighty God to watch over our nation. We pray that he will comfort and console those who walk in sorrow."

The day before, the president designated Friday as a national day of prayer for the thousands of victims of Tuesday's terrorist attacks when hijackers slammed airliners into the twin towers of New York's World Trade Center, the Pentagon outside Washington and rural Pennsylvania.

He called on Americans to attend a service of their choice and "pray for our nation."

At the National City Christian Church in downtown Washington, office workers, many dressed in red, white and blue and holding small US flags, streamed up the stone steps, filling the church beyond capacity.

Ray Short, who lives in the neighborhood, said coming to pray "seemed about the only thing I could do."

A racially mixed crowd sat in silent prayer at the nearby Metropolitan African Methodist Episcopal Church, a traditionally black congregation.

At Saint Matthew's Cathedral, the crowd poured out, filled the steps in front of the massive church and spilled on to the street, leading police to close the road to traffic.

Chrystal Watson braved an unseasonably cold wind to stand outside and worship, in honor of her friends and family here and in New York.

"I pray for the people who lost their lives and for world peace," she said. "I pray for world peace."

A number of area synagogues said they would make special mention of the attacks at their regular Friday night services. The Islamic Center of Washington was to open for regular afternoon Friday prayers after closing for several days after the attacks.