Point by point, White House Special Counsel Gregory Craig and Deputy Counsel Cheryl Mills refuted the evidence against Mr Clinton in an attempt to unravel the House managers' case of perjury and obstruction of justice.

Mr Craig said the allegations of perjury were not legally or structurally sound enough to "remove this or any president from office".

"If you convict and remove President Clinton, on the basis of these allegations no president of the United States will ever be safe from impeachment again," he warned the hushed Senate chamber.

Gregory Craig: "No one should be charged with perjury for asserting their innocence"

The heavily detailed presentations were in sharp contrast to Tuesday's arguments which saw the lead counsel Charles Ruff eloquently deflate House charges as a "witches brew" of allegations.

Mr Ruff's remarks were bolstered by Mr Clinton's 77-minute State of the Union speech in which Mr Clinton proved that it was "business as usual" despite the impeachment trial.

The case for the president

Gregory Craig defends presidential 'nitpicking'

Mr Craig dismissed the charges of perjury as deliberately vague and said it could not be supported by the evidence.

"It is hard to take the charges seriously, when in each case they boil down to arguments over semantics," he said.

Mr Craig also charged that the House prosecutors had stretched far beyond the evidence as well as conclusions made by the Independent Counsel Kenneth Starr.

"What is most remarkable is the fact that that the managers made many, many allegations of grand jury perjury that the independent counsel declined to make," he said.

But it was Cheryl Mills - a 33-year-old African American and the first woman to address the trial - who made the most effective presentation.

In well-modulated rhythm, Ms Mills seamlessly both the obstruction of justice charge and the House case that leaving Mr Clinton in office would undermine the rule of law.

"We've had imperfect leaders in the past and we'll have imperfect leaders in the future," she said citing civil right leaders such as Thomas Jefferson and Martin Luther King Jr.

Cheryl Mills: "The rule of law exonerates the president"

"I can assure you that your decision to follow the facts and the law and the constitution to acquit this president will not shake the house of civil rights."

In answer to the individual charges of obstruction of justice, Ms Mills firmly repeated: "This was not obstruction of justice".

"The president' s intent was never to obstruct justice in the Jones case. It was to manage a looming media firestorm which he correctly foresaw."

Witnesses divide

The BBC's Stephen Sackur: "Still he basks in public approval"

The defence arguments occurred as the Senate appears headed to a partisan clash over calling witnesses.

With this in mind, Ms Mills used her presentation to bolster the credibility of witnesses whose testimony could aid the president like Bettie Currie.

In a discussion of Ms Currie's retrieval of gifts to Monica Lewinksy she stressed that Ms Currie was an honest woman.

"It is an insult to Ms Currie and millions of other loyal Americans to suggest that loyalty breeds dishonesty," she said.

Earlier on Wednesday, senators held separate party meetings and Republicans emerged sounding more sure they will seek to call at least some witnesses during the trial to resolve conflicts in testimony.

"This all doesn't need to go beyond mid-February, even with the deposition of witnesses," said John Czwartacki, the spokesman for Majority Leader Trent Lott.

An invitation to the president to testify was still under discussion.

Clinton flying high

In typical Clintonian fashion, the president continued to ignore the impeachment proceedings.

Mr Clinton and his wife on the way to Buffalo

Earlier on Wednesday, Mr Clinton, Hillary Rodham Clinton and Vice President Al Gore were welcomed by an enthusiastic crowd in Buffalo, New York, where Mr Clinton is pushing education proposals announced in Wednesday's State of the Union speech.

The "business as usual" plan appears to be working in Mr Clinton's favour. New polls show steady support for the president and a continued slide for Republicans.

An ABC News poll taken after the State of the Union speech on Tuesday showed Mr Clinton's approval rating steady at 66% with 77% saying they approved of the proposals outlined in the speech.

It also revealed that 50% of Americans now believe that Mr Clinton will do a better job coping with the nation's ills than the Republicans in Congress.

That is double Mr Clinton's lead two months ago, and the Republicans' worst score in polls since late 1994, after they won control of Congress.