Barnes, 33, has signed a two-year contract and will be available to play in the Champions' League if Newcastle get through the qualifying round against Croatia Zagreb.
Barnes said: "I was very close to joining West Ham. And before I heard of the interest from Newcastle I was virtually certain I was going to join them.
"But once I had heard of Newcastle coming in I explained the situation to Harry Redknapp. I wouldn't have liked to have gone to West Ham with the thought in the back of my mind I had not given myself the opportunity to talk with Newcastle and I explained this to Harry.
"I said to him I couldn't be totally committed to West Ham... and he accepted the situation. The way it has happened it has left me in a very unfortunate situation and I will apologise to West Ham over the whole thing, the way it was actually done."
Barnes was attracted by the chance of playing European football with Newcastle, and Redknapp has refused to criticise him for his decision. Barnes said: "I felt for myself, for my family, for my piece of mind, and also, to be fair to West Ham, I really had to take this decision to come to Newcastle.
"As far as I am concerned and as far as Harry is concerned, who I have spoken too, it is not much of a problem. I don't believe Harry has gone public to criticise me. He is disappointed and rightfully so, it has come out badly, but Harry and I are still friends as far as I'm concerned."
Barnes said he was delighted that Dalglish was giving him a chance at St James' Park, and insisted he can still play an important role for Newcastle. "Newcastle is a huge club, a big stage and I still believe I can perform at the very highest level," he said. "I believe I have still got a lot to offer Newcastle, or any club, but I wish to thank Newcastle for giving me the opportunity to continue my career at the highest level.
"I am coming to a club with a wonderful squad, I have much to offer but the Newcastle players here do also individually and collectively. Kenny is an excellent manager - just look what he has done at both Liverpool and Blackburn - and hopefully what he is going to do here at Newcastle. Every club now needs a strong 18-man squad and this is the aim here. They have wonderful players here."
Barnes added he was not surprised by Newcastle's approach: "It didn't surprise me, I still have confidence in my own ability." The transfer was announced in a statement to the Stock Exchange which said: "The Board of Newcastle United announces that John Barnes, who has been offered a free transfer by Liverpool Football Club, has signed a two-year contract with Newcastle United. No transfer fee is payable to Liverpool."
The 73-times capped England player could make his debut in United's next Premiership fixture, at home to Aston Villa on Saturday 23 August, before returning to Anfield with his new team-mates on Sunday 31 August.
The Hull City team-mates Gregor Rioch and Neil Mann are to get a ticking- off to add to their yellow cards after squaring up angrily at one another in Tuesday's Coca-Cola Cup match at Macclesfield.
The pair , whose antics came on the same night as a similar, better publicised push-and-shove on the cricket pitch at Chelmsford, are to get away with just an admonishment from Hull's new manager, Mark Hateley.
Hateley will not be too hard on his two players, even though they were both embarrassingly booked for the incident in the first-leg 0-0 draw. "I have decided that I won't be fining them for what happened," the former England international said. "In some ways it's nice to see that sort of spirit and commitment in the side. What I did was give them both a telling- off in the dressing room afterwards, and you can be sure it won't happen again. But I think fines is going a bit too far."
The incident happened in the Hull penalty area when the pair fell out in a row about defending a cross. "The lads were both laughing about it when they came off, so there's no long-term problem - team spirit is clearly good," Hateley said.
Rioch, 22, is the son of former Bolton and Arsenal manager Bruce - a fierce competitor himself in his playing days for Derby and Aston Villa - and 25-year-old Mann's father is the former Scottish player Arthur, who played for Manchester City, Notts County and Mansfield in the 1970s.Reuse content