Charlie Sheen and Brooke Mueller have fuelled speculation they are heading for divorce - they have reportedly drawn up a split agreement if the battle to save their marriage fails.

The pair has been largely estranged since a Christmas Day fight landed Sheen behind bars in Aspen, Colorado.

They checked into separate rehab facilities earlier this year for unreleased and unrelated reasons, and when Sheen headed home, Mueller moved out of the estate they shared before their bust-up - causing speculation their split is permanent.

Sheen and Mueller's representatives moved quickly to insist there will be no divorce, but a new report claims the couple has already started preparing for life apart.

TMZ.com alleges Sheen and Mueller are drawing up an agreement covering several personal issues - which will save time if they decide a divorce is inevitable.