In statements posted to YouTube, bassist Alex James says the two tracks "show completely different sides of Blur. There's 'The Puritan', which is a big and bouncy, up and at-em sing-along special. And 'Under The Westway' is more hymn. But I think they'll both go down rather well."
The live webstream, from an undisclosed London roof, will begin at 6:15 p.m. on July 2 and will include an interview with the Britpop heroes. Fans need to follow @ blurofficial for details.
Lead singer Damon Albarn said he's "really excited about getting out there and playing them for people." Both songs will be released on vinyl and download on Aug. 7.
On the Hyde Park show later this summer, James predicts an "emotional show" and one that could mark the end of the band. Or not.
"We certainly get quite overwhelmed by playing the songs, which is something that doesn't happen when you're doing it all the time," he said. "This is something that happens incredibly rarely and who knows if it will ever happen again. Whether this is the end or beginning of the next chapter."
Aside from Albarn and James, Blur also includes guitarist Graham Coxon and drummer Dave Rowntree. The band, formed in 1988, have not released a new studio album since 2003's "Think Tank", which topped the U.K. album chart. Their alternative rock hits in the U.S. include 1994's "Girls & Boys" and 1997's "Song 2", a staple at pro sporting events with its "Woo-Hoo!" chorus.