Harmison took nine wickets in Paarl despite some problems

The 29-year-old arrives in Colombo on Tuesday and could play in the warm-up match against a Board President's XI.

Coach Peter Moores told BBC Sport: "Steve has proved that he's fit, so the next question is whether he's playing well enough to play for his country."

England also have a worry over a back injury to paceman James Anderson.

The Lancashire player could miss the warm-up match against a Board President's XI in Colombo, which starts at 0400 GMT on Tuesday.

Anderson's back stiffened up while he was bowling in the nets on Sunday and Moores said he would take no risks with the bowler, who has been plagued by back problems over the last two seasons.

Steve has got to come here and get involved and it will be good to see where he is at England coach Peter Moores

"The physios feel it is an early twinge but we will be careful with it," Moores said.

"They are expecting him to be better on Tuesday and to be able to take a part in this game, but we will have to wait and see."

Harmison stepped up his recuperation from hernia surgery by playing for South African team Highveld Lions.

He was left out of England's initial squad for Sri Lanka, but the selectors left the door open for a return - providing he was able to fully recover from his injury.

And after talks between Harmison, chairman of selectors David Graveney, Moores and bowling coach Ottis Gibson, it was decided he was fit to join up with the squad for the three-Test series, which starts on 1 December.

Moores said the Durham paceman would not walk straight back into the Test side but admitted he could play.

"Steve will be in the mix with everybody else for that first Test," said the coach.

Moores says he needs to assess Harmison, who took 13 wickets in two matches for Highveld.

Harmison's form has been under the spotlight after a mixed year in 2007, which started with some unconvincing performances in the disastrous Ashes campaign last winter.

Moores told BBC Radio 5 Live: "Steve has proved he can bowl without breaking down and that he's bowling fit, so the next question is whether he's playing well enough to play for his country.

"He's got to come here and get involved and it will be good to see where he is at. It will be good to see him bowl as it will be good to see Michael Vaughan have a bat."

Harmison's form in South Africa had been closely monitored by Gibson, who was impressed with his performances.

The paceman took 6-91 and 3-78 against Cape Cobras in his first match in Paarl, before adding 2-67 and 2-26 against the Dolphins at Potchefstroom.

Sri Lanka, meanwhile, have named a strong Board President's XI squad to face England in their opening tour game.

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The team will be captained by batsman Tillakaratne Dilshan, one of half a dozen players with Test experience included in the 12-man squad.

"England are a very good side and will be very tough opponents," said Dilshan.

"The team comprises some experienced players who are on the fringe and this is a good opportunity to display their talent and ability."

Matthew Hoggard broke down in the first international match of last summer, against West Indies, and made only one of the remaining six Tests of the season.

But he is 100% fit again, and has been out to impress coach Moores and captain Vaughan in the Colombo nets.

Hoggard said the bowlers selected for the matches can expect a tough workout in south Asia.

"The heat and humidity is one of the biggest things, it drains and saturates you more than it does in a dry, hot country or even in England," said the Yorkshire player.