Kimberley Walsh previously admitted that she hopes the group - who went on hiatus in 2009 - will get back together in 2012 to celebrate their 10th anniversary.
The Daily Star claims that the group aim to "capitalise" on Cheryl Cole's rumoured position on The X Factor USA by planning the global gigs.
"Early next year is pencilled in for the reunion tour," a source told the paper. "It's going to be absolutely massive. Cheryl could be a US superstar by then if her appearance on American X Factor goes according to plan this autumn, so they want to capitalise on that.
"It will also be the band's 10-year anniversary in 2012, so the timing is just perfect."
They added: "And with Sarah's wedding being the showbiz marriage of the year, the girls will be back to the height of their fame again."
> Walsh: 'Aloud reunion will be difficult'