WASHINGTON — President Obama moved swiftly yesterday to begin rolling back eight years of his predecessor's policies, ordering tough new ethics rules and preparing to order closure of the detention facility at Guantanamo Bay, Cuba, which has been at the center of the debate over the treatment of U.S. prisoners in the campaign against terror.

Acting on several promises he made during the campaign, Obama met with top generals about speeding the withdrawal from Iraq and gathered his senior economic advisers as he continued to push for a massive government spending bill to create jobs.

He also signed a series of executive orders and directives intended to slow the revolving door between government service and lobbying, and ordered his administration to more freely share information with the public.

Today, he will issue another order calling for the closure of the Guantanamo detention center within a year, an immediate case-by-case review of the 245 detainees now there, and new rules on the treatment and interrogation of prisoners, including compliance with international treaties that the Bush administration deemed inapplicable to suspects in terrorism cases.

On Tuesday, just hours after his inauguration, Obama ordered suspension of all judicial proceedings in the Bush administration's military commissions system at Guantanamo. What will be done with the prisoners is undecided and will be part of the review, sources said. Listed options include repatriation to their home nations or a willing third country, civil trials in this country, or a special civil or military trial system.

Prisoners are to be released or transferred on a rolling basis as soon as the individual case reviews determine whether the detainees can and should be prosecuted, and where.

White House counsel Gregory Craig, who has spent the last several weeks drafting the orders and discussed them with senior Democratic lawmakers in recent days, yesterday went to Capitol Hill to brief House Republicans.

Rep. C.W. Bill Young, R-Fla., said Craig told members of Congress to expect "several" executive orders on Guantanamo, including closing of the prison, but did not provide the specific language.

House Republican Leader John Boehner said in a statement that "there are important questions that must be answered before the terrorist detainee facility at Guantanamo Bay can be closed. The key question is where do you put these terrorists?"

Meanwhile in Cuba, Fidel Castro broke a five-week silence with an essay in which he calls Obama "honest" in his ideas.

The ailing 82-year-old former leader met yesterday with Argentine President Cristina Fernandez.

Hours later, Castro wrote in a statement on a government Web site that he "did not have the slightest doubt of the honesty of Obama ... when he expresses his ideas."

The meeting and essay dispelled rumors that Castro's health had taken a turn for the worse.

He normally publishes his ruminations a few times a week but had not released an essay since Dec. 15, fueling speculation he could have lapsed into a coma.

PRAYERS AND WARS

In addition to the Guantanamo order, sources familiar with the briefings said, Obama will sign two executive orders altering CIA detention and interrogation standards. One will require that only interrogation techniques in the Army Field Manual be used in questioning prisoners, something the Bush administration resisted.

The actions are dramatic evidence that Obama is ready to use his authority and political capital to reverse some of the most controversial practices of President Bush's administration.

They also suggest that the 47-year-old chief executive intends to push quickly for sweeping changes.

"What a moment we're in. What an opportunity we have to change this country," Obama said as he announced new lobbying and disclosure rules during a meeting with his senior staff yesterday.

In a frenetic first full day, Obama was everywhere: alone in the Oval Office, in the front pew at a prayer service, swearing in his staff at the Old Executive Office Building and, for the first time, meeting with his generals in the White House's Situation Room. Obama also welcomed Chief Justice John Roberts to the White House to re-administer the oath of office after the two men fumbled some of the wording during Tuesday's inaugural proceedings.

SEEKING MIDEAST PEACE

Obama's day started with a quiet visit to the Oval Office. After a night of dancing at 10 inaugural balls, he arrived at 8:35 a.m., sitting alone for 10 minutes in one of the world's most famous rooms, aides said.

He read a note Bush had left for him in a desk drawer, a tradition that dates back through several presidencies. The note was in an envelope marked "To: #44, From: #43," according to a statement from press secretary Robert Gibbs, who did not disclose its contents.

Later in the morning, Obama attended the National Prayer Service at the Washington National Cathedral.

But the serenity of the cathedral quickly gave way to the grinding reality of Obama's responsibilities, as he placed calls to Middle East leaders, plunging into an arena he had remained steadfastly silent about during the 78-day transition period.

Sitting behind an almost bare desk in the Oval Office, Obama called President Hosni Mubarak of Egypt, Prime Minister Ehud Olmert of Israel, King Abdullah of Jordan and President Mahmoud Abbas of the Palestinian Authority. Obama pledged "active engagement" in support of the fragile cease-fire between Israel and the Palestinians in Gaza, aides said.

"In the aftermath of the Gaza conflict, he emphasized his determination to work to help consolidate the cease-fire by establishing an effective anti-smuggling regime to prevent Hamas from re-arming, and facilitating in partnership with the Palestinian Authority a major reconstruction effort for Palestinians in Gaza," Gibbs said in a statement.

Today, Obama plans to announce the selection of former Senate majority leader George Mitchell, D-Maine, as Middle East envoy, and former U.N. ambassador Richard Holbrooke as envoy to Afghanistan, Pakistan and for "related matters," sources close to the administration said.

Mitchell, expected to go to the Mideast almost immediately, will be charged with restarting the peace process there after the three weeks of violence between Israel and the Palestinian militant group Hamas.