By Julian Shea

Khan admits he has not yet been fully stretched

Amir Khan says he has decided to challenge for his first major title in his 13th fight to silence people who say he has not yet been tested.

The biggest fight of his professional career will be against Commonwealth lightweight champion Willie Limond at the O2 Arena on 14 July.

"I told Frank Warren I wanted this because I wanted to show people I am a good fighter," he told BBC Sport

"It's the biggest step I've taken and it'll show where I am in the division."

Khan, 20, admitted Limond's greater experience would pose a whole new challenge for him.

"He can take a shot and can come back and give one back," he said.

"When he's hurt he knows what to do, he's a seasoned professional with a lot of experience - that's the only thing he's got on me.

One day when everyone sees me at my best, I'll be untouchable Amir Khan

"He's got a variety of punches and is quick so he's different. I'm going to beat him and show I am a good fighter."

Khan admits that in his 12 professional fights so far, he has not been really stretched, hence his determination to show what he can really do.

"I admit I've not been tested the best, I don't know if this fight will test me, but one day when everyone sees me at my best, I'll be untouchable.

"That's the direction I want to go in and at the moment I'm working on that. People haven't seen anything yet."

Khan has his eyes set on being a world champion in a year's time, and provided all goes according to plan, he already has his progression towards the title sketched out.

"I think in six or seven fights' time I'll be rated in the world top 10," he said.

"Hopefully I can get the Commonwealth title, then British and European then the world - at the moment this test is perfect for me."

British contemporaries such as John Murray and Graham Earl have been eager to criticise Khan as too much hype and not enough substance.

Khan says silencing them with an impressive display against Limond would give him great satisfaction.

"There's a lot of trash talk.

Khan has won all 12 of his professional bouts so far

"Graham Earl thinks he can beat me but this fight should have been with him, but he pulled out just before it was announced," he said.

"People should keep their gobs shot if they don't want to fight.

"I want to prove to people I'm a great fighter and I can beat all these guys - after this fight I think a lot of people will shut up."

Limond, 28, has a record of 28-1, with his only defeat an eighth-round stoppage by Alex Arthur in 2003.

Despite him being the champion, the fight is being sold on the strength of Khan's title bid - but the Scot does not mind that.

"He's a big name, he's box office so I'm not bothered, I know what I've got to do so I'll just train hard and do it - this is the biggest fight I've been involved in, that's for sure," he said.

"Amir's got a lot of speed but I've got experience which counts for a lot."