Jose Mourinho described himself as "the happy one" after being officially unveiled as Chelsea's manager for the second time today.

The Portuguese, who led Chelsea to back to back titles during his initial spell at the club between 2004 and 2007, has signed a new four-year deal to be the Blues’ new manager after leaving Real Madrid.

Mourinho famously described him as a “special one” at his first unveiling nine years ago, but today he was a bit more restrained.

Speaking to about 250 journalists at Stamford Bridge, the 50-year-old said: “I am the happy one. I am very happy.

“Time flies. A lot of things happened in my professional life in the last nine years, but I have the same nature, I am the same person, I have the same heart, I have the same kind of emotions related to my passion for football and my job, but I am a different person in this moment.

“If I have to describe myself, I would describe myself as a very happy person because it’s the first time I arrive in a club where I already love the club.”

Mourinho left the club by mutual agreement six years ago, with many observers pointing to a perceived breakdown in his relationship with owner Roman Abramovich.

But he said today: “First of all, that’s not true. I read and I keep hearing that I was fired, I was sacked, we had a complete breakdown of our relationship – that was not true.

“Many didn’t believe that but it was a mutual agreement. We thought it was best for both of us, for me and the club.”

Mourinho went on to win the 2010 Champions League with Inter Milan, while the Blues themselves won the competition two years later.

“It was a sad moment but I don’t regret that decision because after that I went to Inter, where I had probably the best moment of my career,” said Mourinho.

“After that I went to Madrid where we still have the record of the best team in Spanish history.

“For Chelsea things went well too, after that Chelsea were European champions for the first time.

“It was difficult for both of us but it was made by mutual agreement. Only because there was never a breakdown of the relationship is it possible for me to be here today.

“I think I’m back because we are in the best moments of our careers and ready to work together again. There are much better conditions at this time to succeed and have what we want, stability.”

Mourinho won two Premier League titles, one FA Cup and two League Cups during his three-year spell at Stamford Bridge.

He has now set his sights on achieving even more success during his new period at the club, where he has signed a four-year contract.

“I want to believe it’s possible. I always trust my work,” he said.

“In this case I know many of the people that belong to the club and I know the kind of mentality people have here and my career was built and based on success where I was able to reach success and to win trophies.

“I want to everyone to work hard, work with quality. The club means much more compared to ourselves. We are no one without the club. If we work well success will arrive.”

Mourinho is aiming for a long second spell at Stamford Bridge after spending less than three years at both Inter and Real.

The Portuguese has always spoken of his love of the English game and it appears he is now hoping to settle in the Premier League.

“I am where I want to be so now it’s up to me to work hard to show my club that I deserve to be here for a long time,” he said.

“We have a contract of four years, in the first stage I hope we can look to the last day of his contract and if in the end the club is happy and wants me to stay I will be more than happy to do that.

“I think the culture in football is something very, very important for a manager.

“I did what I wanted to do and as I was saying since six, seven, eight months ago I wanted to go where I really like it very much and I was in a position to say which one is a league I prefer, which one is the club I prefer, which one is the mentality I prefer.

“First of all I decided that I was going to leave my previous club, that was like the trigger and I needed to make that decision and I made that decision.

“After that it was a question of analysing the situation, analyse the possibilities and make the decision which I believe is the best decision for my happiness.

“So when the Chelsea situation appears really and strongly, decision made.”

Mourinho is keen to reestablish club captain John Terry as a key figure in the team, after the central defender was marginalised at times last season under interim boss Rafael Benitez.

“From me, (there will be) not one word about Benitez’s decisions, on John or any other player,” he said.

“What I can say is about the future – (I’ll) meet John in the first week of July and try to get the best out of him.

“I know what he can give, let’s try to make him again a very important player which he couldn’t be last season.”

Terry’s situation was mirrored in Madrid last season as Mourinho left Real and Spain captain Iker Casillas on the substitutes’ bench for much of the season.

But the coach insists there was no fall-out with the goalkeeper and that he will assess each player on his merits.

“I play the players I think are the best for the team,” he said. “If I think somebody deserves to play, he has to play. If somebody has a big profile, a big stature, a big career, I cannot give him a privilege.

“It was a football decision, I decided for one player and not the other and it is up to the player to accept it or not. All my decisions are based on meritocracy, then I can sleep well.”