Rolling Stones will not play Glastonbury Festival in 2013 but they were invited

The Rolling Stones at the exhibit opening of "Rolling Stones: 50" in London on July 11, 2012. Pictured from left to right: Charlie Watts, Keith Richards, Ronnie Wood and Mick Jagger.

The Rolling Stones will not be playing the 2013 Glastonbury Festival in England, say sources close to the band. British tabloid The Sun feuled the rumor by publishing a story saying that the Stones were close to signing a deal to perform at the festival. It's true that Stones were invited to perform at Glastonbury, but it's not true that they are close to signing a deal, and the band won't be performing at the festival in 2013.
Every year, there are false rumors that the Stones will be performing at a major music festival. These rumors are usually started by the festival promoters/organizers who have invited the Rolling Stones to perform at the festival and hope that the band will say "yes" if the story is put out in the media that the Stones might perform at the festival. The rumors are started to generate public interest and boost ticket sales for the event, since there are gullible fans who will buy tickets "just in case" the Stones perform at the festival.
The Coachella Festival is notorious for this kind of publicity stunt. The Rolling Stones have never played at Coachella and have no plans to do so, but that hasn't stopped rumors from spreading every year that the Rolling Stones are "close to signing a deal" to perform at the festival. And these rumors are spread even when the band isn't on tour the year that the Stones will supposedly play at the festival. It's unrealistic that Stones would end a hiatus just to play at a festival in which they are one of many acts on the bill.
Here's what an unnamed source told The Sun about the Stones performing at Glastonbury in 2013: “The band are gearing up for a load of live dates but tend to leave big decisions like this until the last minute. Michael Eavis is desperate to get the band confirmed and has made initial contact with their people. It would be a massive coup to get the band playing Glasto on what could be their last round of live dates. Getting a decision from the whole band can be tough and at the moment they are without an agent for live shows, which is not helping the situation. But there is a good chance 2013 will finally be the year they make it.”
Take that information for whatever you think it's worth. Until an official announcement is made about the Stones doing concerts in 2013, it's best to be skeptical of these tabloid stories. As of now, the Rolling Stones have not confirmed any concert dates for 2013.