He was speaking to reporters in his home town of Carthage, in the state of Tennessee, as he prepared to launch his own year-long campaign for the presidency.

Mr Gore said the consequences of the president's affair with the White House trainee, Monica Lewinsky, had put a strain on his relationship with Mr Clinton.

He said he had had to show steadfastness during a difficult year, and he questioned whether all the disruption need have happened.

He said that, as a parent, he found the whole episode "inexcusable".

Vice-President Gore:"Should we have had to go through it? No."

"I've kept it to myself because I took an oath under the Constitution to serve my country as vice- president - which means helping Mr Clinton to be the best president he can be, not arguing with the policies of the administration," he said.

A different vision

"But everything changes on Wednesday, when I become a candidate, because I will be describing my own vision for the future. If that happens to be different from what the administration wants, I think that's understandable to people."

President Clinton supports his deputy

Political observers say that one of the challenges facing Mr Gore is to run on the successful policies of the Clinton administration, without being tarred by its scandals - including the Monica Lewinsky affair, that led to the president's impeachment.

But they say the vice-president's image as an upstanding husband and father is unchallenged.

He holds a solid lead in the opinion polls, as well as money raised, over his only Democratic rival, former Senator Bill Bradley of New Jersey.

But there is concern among Democrats about his ability to win the presidency.

The polls show him trailing the top two Republican candidates, Texas Governor George W Bush and former American Red Cross President, Elizabeth Dole.

Despite this, he appears to enjoy the full support of the Oval Office. Mr Clinton has described his deputy as the most active vice-president in US history.

According to Mr Gore's campaign spokesman Robert Salazar, the vice-president intends to be more specific about his positions and plans this week, during meetings with voters in Iowa and New Hampshire - the states that will cast the first votes in the 2000 presidential election.