The singer joined the group as the replacement for Keisha Buchanan in 2009 and, together with Heidi Range and Amelle Berrabah, released the album Sweet 7 the following year.
Asked if the group would record new music, Ewen told Flavour Magazine: "We do have plans to do so. There's so much happening at the moment.
"I'm doing [web drama] Steffi as well as a solo project which I am really enjoying, and I think I can say the same for Heidi and Amelle."
She added: "We're all just kind of taking the opportunity to explore other areas and aspects of our careers.
"I think we will probably come back together again at the end of the year. There will definitely be more recording, but there is no release date any time soon."
Last year, Range told Digital Spy that she and her bandmates were "all writing in the studio anyway" and described the Sugababes project as "kind of ongoing".
Asked if she was worried about other groups reforming, Ewen continued to Flavour Magazine: "No, I think it's encouraging. If groups can come back and still enjoy success then great for them.
"At the moment, everything is just competition, especially when you look at the internet and shows like The X Factor where there are new talents constantly emerging.
"You've just got to get on with it and do it for the right reasons; if you make good art, then I think people will see that, and it will shine through rather than being famous for five minutes."
While the current Sugababes are on hiatus, the founding lineup of Siobhán Donaghy, Mutya Buena and Keisha Buchanan have reunited and are now recording music as Mutya Keisha Siobhan.
Watch the Sugababes 'Wear My Kiss' music video below: