“It's inescapable that this is the second most important day in Westfield history. The most important day was in September 1960 when Westfield was born,” he said. “Most know the history of Westfield’s humble beginnings of a humble store in Blacktown, which is still there. “Who would have thought that 57 years later I’d be sitting in snowy London talking to you in Sydney like this, certainly not me. “I was just 29 years old and I did not know much believe me, and not sure I know much more now.” Loading Replay Replay video Play video Play video

Empire building Sir Frank's decision to stand back marks the closing stages of one of the most successful careers in Australian business. Along with then business partner John Saunders, he built up their Westfield shopping centre empire from scratch in Australia in the 1960s, before expanding to the US, New Zealand and the UK. The empire was split in 2014, with the international business continuing to be run by Steven and Peter Lowy, and the Australian and New Zealand malls spun off into the separately listed Scentre Group.

Sir Frank cut all ties with Scentre last year but remained at the helm of Westfield Corp.Steven Lowy is still on the Scentre board and the family retains a 4 per cent stake in the local shopping centre operator, and just under 10 per cent of the international business. The Lowy family has agreed not to sell its interest in Westfield while the deal is underway, and to vote in its favour provided the board doesn't recommend a superior proposal and an independent expert finds it is in the best interests of Westfield securityholders. The family said it was committed to the success of the group and planned to keep a substantial investment in it. "Unibail-Rodamco's track record makes it the natural home for the legacy of Westfield's brand and business," Sir Frank said. "We look forward to seeing Westfield continue to grow as part of the world's premier owner of flagship shopping destinations."

Westfield securityholders will receive cash and shares in Unibail-Rodamco,valuing Westfield at $US7.55 ($10.01) per security - a 17.8 per cent premium to Westfield's closing price on Monday. Unibail-Rodamco holds a 4.9 per cent economic interest in Westfield securities. Existing Unibail-Rodamco shareholders will emerge with about 72 per cent of the combined group and Westfield securityholders will hold about 28 per cent. Its securities will be listed on the ASX, as well as in Amsterdam and Paris. The deal, which is expected to close in the first half of 2018, is subject to court and shareholder approvals. OneMarket spin-off

Westfield will spin off 90 per cent of its retail technology platform OneMarket into a new ASX-listed entity before the deal is completed. The combined group will hold the remaining 10 per cent of OneMarket, which will be chaired by Steven Lowy, with Don Kingsborough as chief executive. "OneMarket has been developed within Westfield and it has always been envisaged that it would be separated at the appropriate time," the statement said. Corporate activity The takeover of Westfield would continue the recent spate of corporate activity among US real estate investment trusts, with Brookfield Asset Management looking to acquire all the shares it doesn't already own in General Growth Properties and the New York fund manager Third Point taking a stake inMacerich Co.

Wesfield has been under pressure to get its debt down and that has been a focus of the management. JP Morgan's Westfield analysts noted the increased activity in the regional mall space globally, with mergers and acquisitions, shareholder activism and buying from well-known value investors. ''This activity is reflective of a sector trading at material discounts to fundamental valuations. We believe the high-quality mall space has been oversold on the risks around Amazon and long-term structural challenges,'' JP Morgan's analysts said. ''We believe Westfield has amongst the best retail portfolios globally, and is improving it via redevelopments at its best assets.''