England's all-time leading Test wicket-taker will miss Lancashire's next two four-day County Championship matches against Northamptonshire and Sussex after complains of tightness in his right calf muscle.
The 36-year-old Anderson underwent an MRI scan on Friday, with an ECB spokesman confirming: "The MRI confirmed that Anderson has suffered a low-grade calf muscle tear.
"As a result of the injury, he will commence a rehabilitation programme with the England and Lancashire CCC medical teams."
The spokesman further added: "He will be reassessed on an ongoing basis regarding his availability for the Specsavers Test match versus Ireland at Lord's on July 24 and the Specsavers Ashes Series against Australia starting on August 1."
Anderson’s absence will be a massive blow for England as lies fourth in the all-time list of Test wicket-takers.
The Ashes series kicks off on August 1 with Edgbaston being the venue for the first Test.
Australia hold the Ashes currently but they have not won a Test series in England since 2001.