As the prosecutors completed their opening arguments they intensified their efforts to persuade US senators to allow the summoning of witnesses, like Monica Lewinsky, whose affair with the president led to his impeachment.

On the second day of arguments in the majestic Senate chamber, House prosecutors again tried to persuade senators that the "big picture" proved Mr Clinton had consistently perjured himself and obstructed justice to keep his relationship with Monica Lewinsky a secret.

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"I would encourage you never to lose sight of the totality of this scheme to lie and obstruct justice. Never lose sight of the big picture," Florida Rep Bill McCollum said in his summary of the facts.

"The president engaged in a scheme starting in December 1997 to conceal from the court in the Jones case his true relationship with Monica Lewinsky and to cover up his acts of concealment, which he had to know by that time were serious crimes."

Rep McCollum: Evidence shows Mr Clinton "knowingly" lied

Mr McCollum was supported by four House colleagues who, with a blizzard of charts, discussed the law and penalties of perjury and obstruction of justice.

But it was Rep Bob Barr of Georgia who summed up the House case after a lengthy recounting of how Mr Clinton allegedly tried to get Ms Lewinsky a job.

"What are you as jurors entitled to conclude from all of this as a matter of law and fact?" he said. "Mission accomplished. Obstruction accomplished."

Bill McCollum: "Clinton's lawyers will say he didn't cross the line intentionally."

Surprisingly, the day's most dramatic moment came from a Senator, not a House prosecutor.

Democratic Sen Tom Harkin stunned his colleagues by interrupting Rep Barr's presentation by objecting to being called a juror. He said he did not want to go down in history as a juror in a trial that had no right to take place.

Chief Justice William Rehnquist sustained the motion, agreeing the Senate "is not simply a jury but a court."

Boredom burdens prosecution

Despite the historic nature of the trial, prosecutors face an uphill battle.

The second full day of the trial seemed to capture less of the nation's interest. Major television networks that carried the start of Thursday's session did not do so Friday. The Senate gallery, packed on Thursday, was three-quarters full.

A new ABC News poll showed that only 33 percent believed Mr Clinton should be removed from office if he lied about the affair under oath, compared to 55 percent who held that position shortly after the scandal first broke one year ago.

President Clinton, meanwhile, was in New York as the proceedings began. In classic Clinton style, he tried to make it "business as usual" by unveiling an economic initiative for inner cities.

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Speaker after speaker at Clinton's appearance at the World Trade Center heaped lavish praise on him. Mr Clinton called it "the sort of thing people say for your funeral."

"I don't think we're there yet," he added with a laugh.

Witnesses still divisive

Rep McCollum also used his time to keep up pressure on senators to call witnesses by trying to highlight possible conflicts in testimony that could be resolved only by hearing from the people themselves.

"If you have any significant doubts about Monica Lewinsky's credibility or her testimony, you should bring her in here and let us examine her face to face so you can judge her credibility for yourself," Rep McCollum said.

The issue of witnesses has polarised the Senate. Democrats have argued the mountain of evidence passed on from the House should serve as the official record.

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"It was the same thing I've heard in the House for the last three months," said New York Democrat Charles Schumer. "I think some in the House hope that if they keep saying it enough maybe public opinion will change. "I don't think so."

'Above the law'

Mr Clinton is charged with committing perjury and obstructing justice over his affair with former White House aide Monica Lewinsky.

After the conclusion of Friday's evidence, Republican Sen Arlen Specter of Pennsylvania said the prosecutors had presented a compelling case.

"Unless the White House can rebut some of these arguments, the senators are going to have a hard time voting against removal from office."

Mr Specter added that he would like the president to come to the Senate floor and explain himself. But he said he believed that was "zero chance" the president would do so.

The 13 House managers have 24 hours to present opening arguments against the president. White House lawyers are expected to begin their opening statements on Tuesday, 19 January.