Montgomery breaks the world 100m record last September

World 100m record holder Tim Montgomery and Olympic champion Maurice Greene have clashed ahead of the US trials.

"I don't respect anyone who doesn't respect me," Montgomery told reporters when asked about Greene at a news conference.

"Would you like to have your world record back?" Montgomery called out to his great rival.

"I will get it back," replied Greene.

Montgomery believes that he is back in shape after a difficult winter, when he split from coach Trevor Graham and briefly linked up with Ben Johnson's former coach Charlie Francis.

"Four months ago, five months ago, I thought about calling it a season," he said.

"I was going through a lot of things. Now the rain and clouds are starting to spread and the sun is starting to come back out.

"If I don't have a headwind, you are going to see some stuff out of me come Friday (in the 100m final) you haven't seen in a long time."

Greene will run just the 200m at the trials, because he is guaranteed a 100m berth at the Worlds as the reigning champion.

Greene has been in blistering 100m form this summer

"Why is he concentrating on the 200m when the world record is in the 100m?" Montgomery asked. "If he wants the record back, I want him to come and get it.

"I respect his running but I don't respect him as a person. As an athlete he is impeccable, but as a person who doesn't respect the other seven people on the track, I don't have any respect for him."

Greene hit back when made aware of Montgomery's comments.

"I respect everybody," he said. "The minute you stop respecting people is the minute you are going to have a hard time. Anything can happen when you step on the line."

Training partner, Jon Drummond, has warned Greene's rivals not to underestimate the Olympic and double world champion.

"To all those who say that Maurice is washed up, they're a bunch of fools who want something to say to excite conversation on the internet," Drummond said.

"All Maurice does is use that as energy to come out here and run fast and prove them all wrong."

Montgomery also defended his decision to work with Francis.

"Whatever happened to Ben Johnson, he (Francis) still had to have some kind of technique and talent to carry him to 9.79 seconds. I just wanted to hear the technique.

"I was not going to go find someone who had someone who ran 10.20. I am trying to go faster.

"I did not leave Trevor Graham - Trevor Graham called and left me. The record needs to be set straight."

Montgomery and Greene are likely to meet for the first time in Paris on 4 July.