MEMPHIS (From news reports) -- DS Smith PLC and International Paper Co have cleared a regulatory hurdle on the way to their proposed combination, the firms proclaimed on Tuesday.

London-based packing company DS Smith agreed an all-share takeover by its Memphis, Tennessee-based rival in April, which would leave its shareholders with 33.7% of the combined group and values each DS Smith share at 415 pence.

On Tuesday, DS Smith and International Paper announced that the waiting period under the Hart-Scott-Rodino Act has expired.

"This is an important step in the consummation of the proposed combination as the expiration removes the HSR Act's bar to closing," the companies explained.

The HSR Act is a US antitrust law, requiring companies to file a pre-merger notification report with the Federal Trade Commission and the Department of Justice before a merger or acquisition occurs.

International Paper and DS Smith said completing the takeover remains subject to the satisfaction or waiver of various remaining conditions, including regulatory clearance by the European Commission and a court sanction of the scheme.

Both companies said they still expect the scheme to come into effect during the fourth quarter.