The HQ building in Shanghai is more than twice the size of Dundrum Town Centre and the biggest asset of Treasury China Trust (TCT), a Singapore listed business in which Mr Barrett and Mr Ronan have a 30 per cent share.
Gross income for 2012 from the asset is expected to be circa €32.4m, the update in December said.
The announcement is bound to have fired up the attention of Nama and KBC in relation to the complicated and arduous Treasury Holdings liquidation process.
While TCT is not subject to that liquidation, Treasury Holdings-linked assets in Asia are being monitored by Treasury's liquidators and core creditors. They will be keen to track any assets the duo have that might serve to pay down their debts.
In court proceedings due to continue in February, Nama is seeking to reverse the disputed TAIL (Treasury Asian Investments Ltd) transaction. This involved the alleged transfer in 2010 of 20 million shares in TCT into TAIL, a subsidiary, to the benefit of Mr Barrett and Mr Ronan, for €100,000 and unsecured loan notes.
At that time the value of the TCT (then called CREO) shares involved greatly exceeded the value of that deal, according to Nama.
Treasury Holdings' liquidator is joining Nama in pursuing an action against the duo to undo the transaction. It says there was no commercially valid reason for the move, made when Treasury was either insolvent or in severe difficulty. The transaction impaired the rights and interests of Nama as major creditor of Treasury, it is alleged, though Treasury denied this.
The giant retail mall and three office towers in Shanghai comprises 176,000sqm in space, and another 88,000sqm is being built. When complete it will be an integrated commercial complex comprising 264,000sqm and is expected to produce a gross rental yield of 10 per cent per annum.
Retail tenants are expected to move in before the end of 2013 and 42 per cent of the retail space of the building has been pre-leased. Existing office space of 85,000sqm is 94 per cent occupied.
Treasury China Trust is managed by and pays significant fees to Treasury Holdings Real Estate (THRE), a management company which was acquired from Treasury Holdings by a Jersey-based company owned by Mr Barrett in August, just ahead of KBC's winding up order. The acquisition price of €2.2m has been queried by KBC and Nama. An earlier valuation by Goldman Sachs suggested a value of over €38m.
A recent meeting of the board of THRE approved TCT's 2013 business plan. The completion of The HQ is "at the heart of the strategy to ensure long-term value for unit holders and an expected return to a policy of consistent distributions not later than 2015", the executive summary of that meeting said.
TCT owns €2bn worth of office and retail property assets in China, Shanghai and Beijing. It has a market capitalisation of €245m.
Meanwhile, Nama appointed PWC as fixed charge receiver to the five-star Westin Hotel in Dublin city centre last week. The hotel's operator, Starwood, and the trading of the hotel will not be impacted by the move by Nama to tighten its grip on properties formerly owned by Treasury.
Treasury businesses owe Nama €1.7bn and KBC €72m.
None of the parties involved responded to requests for comment.