Dallas, who can also operate as an attacking midfielder, was a key player in Northern Ireland’s 2018 World Cup qualifying campaign.
The 26-year-old has stated that Michael O’Neill’s side booking a place in the playoffs is a big achievement.
“We’ve got to the play-offs, which in itself is a big achievement, but we haven’t got there (to the World Cup finals) yet,” Dallas told Irishfa.com.
“We have a couple of big games now next month and hopefully we can get over the line.”
Dallas is one of the best players in the Northern Ireland national football team, and the Leeds winger will be key for them in the playoffs.
The 26-year-old former Brentford star has played well for Leeds so far this season despite not starting too often.
The former Crusaders attacker is one of the best wingers in the Championship, and he will expect to start regularly for Leeds as the season progresses.
Leeds are fifth in the Championship table at the moment with 20 points from 11 matches.
Thomas Christiansen’s side will return to action on Saturday afternoon when they take on Reading at Elland Road in the league.