The original deal was announced in January 2005 as being worth $445m, but this has been slashed to $405m because of Pittsburgh, Pennsylvania-based Mellon’s sluggish HR consulting revenues.

Dallas, Texas-based ACS said the all-cash transaction will be funded from its existing $1.5bn credit facility, but it also announced that it has commenced an offering of $500m in senior notes as it restructures its debts.

ACS said it expects the acquisition to be accretive in its fiscal year 2006, which begins on July 1, 2005, by $0.04 to $0.06, rising to $0.20 to $0.24 the following year.