Australia fast bowler Ryan Harris has announced his retirement from all cricket effective immediately.

Scans in London yesterday confirmed new damage to his battle scarred right knee, forcing him out of the the 2015 Ashes series in the United Kingdom.

Young NSW Blues quick Pat Cummins has been confirmed as Harris' replacement for the remainder of the tour.

Harris has endured a string of chronic knee problems throughout a career that has seen him progress from a hard-hitting batting all-rounder who bowled some handy medium-fast into one of the most potent new-ball bowlers in world cricket.

Read more at Cricket.com.au