Former Ireland captain Trent Johnston says he has returned to national duty to help his side qualify for the ICC World Twenty20 to be staged in England next year.

'I made myself available because I want to help Ireland reach next year's ICC World Twenty20,' he said.

'I didn't make myself available for the recent ODIs because I thought, when I wouldn't be around for the ICC Cricket World Cup 2011, it made no sense in me playing in those matches.

'All I would have been doing was denying someone a place who can be groomed and prepared for the tournament to be held in the Asian subcontinent,' said Johnston, ahead of the ICC World Twenty20 Qualifier to be staged in Belfast, Ireland from 2 to 5 August.

Johnston stepped back from international action after Ireland's tour of Bangladesh in March. He has missed the ODI tri-series against New Zealand and Scotland, ICC Intercontinental Cup and Friends Provident Trophy matches and the ongoing ICC European Championships being played in Dublin.

Johnston has also been recalled for Ireland's ICC Intercontinental Cup against Canada to be played in Malahide, Ireland from 6 to 9 August. He is not in the side for the 12 August ODI against the same opposition after again making himself unavailable.

Top seeded Ireland are grouped with Scotland and Bermuda while the other group is formed of Kenya, the Netherlands and Canada as the top six Associate teams go ahead to head in the four-day tournament at Stormont where at stake will be two or possibly three places in the England event.

Both finalists will qualify for that tournament which will take place at Lord's, The Oval and Trent Bridge next June while the third place, to be decided by a third and fourth-place play-off, is dependent on Zimbabwe Cricket's Board ratifying a decision taken by its officials during ICC Annual Conference week, to step back from the tournament.

Johnston has an impeccable record as an Ireland cricketer. He has played 23 ODIs, 16 first-class and inspired his side to successive victories in the ICC Intercontinental Cups in 2006 and 2007.

However, Johnston's finest cricketing moment came at the Sabina Park in Kingston, Jamaica when he hit the winning runs in Ireland's famous victory over Pakistan in the ICC Cricket World Cup 2007.

Ireland followed up that victory with a win over Bangladesh in the same tournament that allowed it to enter the Reliance Mobile ICC ODI Championship table where it is currently placed 10th, ahead of Bangladesh and Kenya.

The 34-year-old said his own fitness and job commitments were also the combining reasons for taking a step back from one-day and four-day matches. 'I decided to step down because my body was telling on me and my job commitments were not allowing me to stay out of the office for longer periods of time.

'I underwent surgery on my bowling arm after the Bangladesh tour and now I am trouble-free. But I completely back my decision to withdraw from one-day matches.

'I can't have the right to pick and choose the matches. I think my decision has benefitted everyone, especially Phil Simmon (team coach) who can prepare the team for the future,' said Johnston, who also played for New South Wales in Australia's Sheffield Shield in the late 1990s.

While one of Johnston's finest moments was that victory over Pakistan, one of his worst times came in Nairobi in January-February 2007 when Ireland finished fifth in the ICC World Cricket League Division 1 and consequently failed to qualify for the inaugural ICC World Twenty20 in South Africa last year.

Johnston admits the Nairobi tournament still hurts him. 'It was heart-breaking, demoralizing and devastating. We had left no stone unturned in our preparations but in the tournament, we lost four matches in their closing stages,' he recalled.

Ireland suffered defeats against Scotland (by three wickets), Kenya (by one wicket), Canada (by six wickets) and the Netherlands (by six runs) while its only victory was against Bermuda (by four wickets). The tournament was won by Kenya, which defeated Scotland by eight wickets.

'As a captain it was depressing, while the players also took it to heart. But I guess, the Nairobi tournament made us a better, tougher and stronger team because afterwards we won important matches.

'We buried to ghost of the Nairobi tournament at Sabina Park when we defeated Pakistan. But yes, we still rue the lost opportunity of playing in the ICC World Twenty20 in South Africa,' he said.

Johnston said the Twenty20 format was beneficial to Associate teams. 'There is lot of focus and attention on Twenty20 cricket and I think this is the format in which the Associate countries can make a name for themselves.

'I don't think there will be any clear-cut favourites in Belfast, and we saw that in South Africa where Zimbabwe defeated Australia. The bottom line is the team has to be on top of its game for the entire 40 overs to win the match.

'There is no time to relax. One wrong decision, one bad over and it could be all finished. But this is an exciting format and will definitely help the developing teams,' he said.

Ireland, which has eight players from the ICC Cricket World Cup 2007, is at full strength for the Belfast tournament.

The side will be by 23-year-old left-handed batsman William Porterfield, who plays for Gloucestershire in the county championship in the UK.

Porterfield has not captained Ireland in an ODI or ICC Intercontinental Cup match but has led his team in five Friends Provident Trophy tournament matches in the UK

Although his side lost four of the matches, Porterfield inspired Ireland to a four-wicket victory over Warwickshire, its first win over a county side in two years. Porterfield scored 69 in that match as Ireland achieved the target of 212 in 46.4 overs in Stormont.

Other players with vital county championship experience are left-handed batsman Eoin Morgan (Middlesex), wicketkeeper-batsman Niall O'Brien (Northamptonshire) and all-rounder Andrew White (Northamptonshire).

Off-spinner Kyle McCallan is Ireland's most capped player with 28 ODIs. Fellow spinner Gary Kidd and wicketkeeper-batsman Gary Wilson (currently on Surrey's staff) are some of the emerging cricketers who have benefited from a trip to India earlier in the year for the ICC European Cricket Academy.

IRELAND - Wiliiam Porterfield (captain), Niall O'Brien, Eoin Morgan, Kevin O'Brien, Andre Botha, Andrew White, Alex Cusack, Gary Wilson, Trent Johnston, Kyle McCallan, Thinus Fourie, Peter Connell, Philip Eaglestone, Gary Kidd.