(Adds Barr, Rosenstein at Justice Department)

By Andy Sullivan

WASHINGTON, March 24 (Reuters) - U.S. lawmakers drew battle lines on Sunday over how to handle a special counsel long-awaited report on Russian meddling in the 2016 election that has cast a pall over Donald Trump's presidency and raised questions about collusion between his campaign and Moscow.

Members of Congress, the media and Trump himself were waiting for Attorney General William Barr to release a summary of the report by Special Counsel Robert Mueller after his 22-month investigation of Russian connections.

Trump, who decried the probe as a witch hunt and waste of time, was at his resort in Palm Beach, Florida, where he went to his golf club on Saturday and Sunday but remained uncharacteristically silent about Friday's conclusion of the Mueller probe.

Barr, the top U.S. law enforcement official, spent nine hours on Saturday studying the report. He and Rod Rosenstein, the deputy attorney general who appointed Mueller, were at the Justice Department again on Sunday.

Barr said he hoped to make public a summary of its "principal conclusions" over the weekend. The White House has not received or been briefed on the report, spokesman Hogan Gidley said on Sunday morning.

Whatever the report concludes, Democrats vowed to pursue investigations on a wide range of issues involving Trump, from his business dealings to hush-money payments.

They called for the full release of the report, as well as documents backing up its findings, and have promised to subpoena any information they do not get. Many Republicans also want the report released and say it will vindicate Trump. Some cautioned portions of it might need to remain confidential.

There appeared to be initial good news for Trump and his inner circle, as Mueller did not bring any additional indictments when he handed the report over to Barr on Friday.

That signals there might be no more criminal charges against Trump associates on the issue of whether the Trump campaign conspired with Russia to help the real estate magnate beat Democrat Hillary Clinton in the 2016 presidential race.

Democratic and Republican lawmakers disagree about whether no criminal charges meant there was no cooperation between the Trump campaign and Moscow.

Mueller's court filings already showed a number of top Trump aides had contact with Russians during the campaign and after the election and that some of them lied about it.

"We know there was collusion. Why there's been no indictments we don't know," U.S. Representative Jerrold Nadler, the Democratic chairman of the House Judiciary Committee, said on CNN's "State of the Union."

Such comments reveal Democrats are determined to try to "go after" Trump, said Senator Ted Cruz, a Republican on the Senate Judiciary Committee.

"What they're basically saying is that they're going to impeach the president for being Donald Trump," he told CNN.

Democratic leaders in Congress have rejected talk of impeachment as premature.

However, House Intelligence Committee Chairman Adam Schiff, a Democrat, told ABC's "This Week" that his panel has a particular obligation to determine whether Trump was "compromised in any way, whether that is criminal or not."

UNANSWERED QUESTIONS

It was not known what Mueller's report says about another key point: whether Trump committed obstruction of justice to hinder the Russia investigation by acts such as firing FBI Director James Comey in 2017.

U.S. intelligence agencies concluded shortly before Trump took office in January 2017 that Moscow meddled in the election with a campaign of email hacking and online propaganda aimed at sowing discord in the United States, hurting Clinton and helping Trump.

Mueller brought charges against 34 people and three companies during his investigation, with prison sentences for some of Trump's former aides such as campaign chairman Paul Manafort and longtime personal lawyer Michael Cohen. None of those charges, however, directly related to whether Trump's campaign worked with Moscow.

Trump took White House counsel Pat Cipollone and Emmet Flood with him to Florida. His only public statements on Sunday were two tweets: "Good morning. Have a Great Day!" and "Make America Great Again!"

Trump denies collaborating with Moscow or obstructing justice. Russia says it did not interfere in the election.

Trump and his team still face legal risks even if the report does not find that they committed crimes, and congressional Democrats on Saturday vowed to keep looking into his activities.

Trump's business, including negotiations over building a Trump tower in Moscow, his charity and his inaugural committee remain under investigation.

Other prosecutors have picked up strands of the Mueller probe, most notably the U.S. Attorney's Office for the Southern District of New York, which is looking into Trump's business practices and financial dealings.

Barr told lawmakers on Friday that he is "committed to as much transparency as possible."

Senator Marco Rubio, a Republican, urged the same from the White House. "The best thing for the country and for the president is for this probe to move forward and to be concluded," he said on NBC's "Meet the Press." (Reporting by Andy Sullivan and Sarah N. Lynch; by Roberta Rampton in Palm Beach, Florida; Karen Freifeld, Doina Chiacu and Nandita Bose in Washington; Editing by Bill Trott)

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