UPDATE 2-Emaar says merger to boost finances, shares drop

* Proposed entity to have assets of $53 billion

* Emaar assets end-March at 68 bln dirhams, debt 10 bln

* Shares down nearly 10 percent

(Adds analyst quotes, background, byline)

By Raissa Kasolowsky

DUBAI, June 28 (Reuters) - Dubai's Emaar Properties EMAR.DU said a merger with real estate units of Dubai Holding, owned by the emirate's ruler, would shore it up financially but shares fell as investors feared they may lose out in the deal.

The proposed new entity combining Emaar with Dubai Properties, Sama Dubai and Tatweer, would have debt obligations equivalent to around 7 percent of total assets, compared with Emaar's 15 percent at the end of March, Emaar's chairman Mohammed Alabbar said in a statement on the bourse website.

But shares in Emaar, the largest listed Arab developer, lost nearly 10 percent as investors worried about asset valuations in the deal and risks in the Dubai real estate sector, which suffered a sharp correction in the global financial crisis.

"The merger is more a way of reducing cumulative costs and supply, which is good, but in doing so [Emaar] is taking up bigger execution challenges, potential for equity raises to finance debt repayments and being less diversified," said Saud Masud, real estate and construction analyst for the Middle East and North Africa at UBS.