Clayton Utz and Herbert Smith Freehills are leading Japan Post Co. Ltd.'s proposed $5.1 billion takeover of Australian logistics company Toll Holdings Ltd.

Japan's state-owned postal service is offering $7.05 a share, or a 49 percent premium to Tuesday's closing price, for Toll as it seeks growth in overseas markets. A declining Japanese population and consumers' increased use of the internet for shipping has weighed on business at home, Japan Post said in a statement. Last October, the company took its first steps into the international market when it entered into an alliance with France's GeoPost SA and Hong Kong's Lenton Group Ltd.

Toll said that its board of directors had unanimously approved the deal and recommended that shareholders do the same. A shareholders meeting is expected to take place in April, with closure of the deal coming the following month. If shareholders give their approval, Toll will operate as a division of Japan Post and retain its name. Toll management will remain in place as well.