The present invention provides methods and apparatus for expanding a first, smaller diameter tubular into frictional contact with a second, larger diameter tubular or wellbore. In an embodiment, annular formations formed on an inner surface of a split ring engage an outer surface of the smaller tubular. In one aspect, the smaller diameter tubular is provided with an annular recess there around, the annular recess including recessed grooves formed there around. Therefore, the split ring is disposable within the annular recess and the annular formations formed on the split ring are constructed and arranged to fit within the recessed grooves of the annular recess of the tubular. An outer surface of the split ring is provided with teeth or some other grip-enhancing material or formation. The split ring also includes a split portion permitting the ring to expand in diameter as that portion of the tubular is expanded in diameter.