The singer explained that although there are currently no plans for the reunited girl group to record a new album, they will never fully leave the band.
"I don't think we're ever going to split up," Walsh told BBC Newsbeat. "I don't think any of us know what's going to happen after the tour. That's as far as we've planned for now."
Cheryl Cole recently concluded her new autobiography by hinting that Girls Aloud would call it a day once their 10th anniversary tour finished.
"Cheryl wrote the book a long time ago," Walsh said. "She obviously wrote it before any of the music, before we had anything in place."
Speaking about plans for after their UK tour, she added: "I think we'll see where we're at then.
"Whether we go back to doing our solo projects for a while, then come back together again… we'll see how it goes and leave it open.
"We're in a really privileged position where we can be like, 'Let's do that for while, let's do that for while.' It's the Take That way - it works really well."
Girls Aloud will release their new single 'Something New' on November 19, while new retrospective collection Ten will follow on November 26.
Watch the music video for Girls Aloud's 'Something New' below: