British mall deals may fall a billion pounds short of a previous forecast maximum of 5 billion pounds as concerns over the euro zone debt crisis dampen investor demand, property consultancy Savills said.

Savills expects shopping centre deal volumes to be 4-4.5 billion pounds by end-2011, down from a previous prediction of 4-5 billion pounds that it made in July, it said in its quarterly retail property report published late on Monday.

Investors that are in 'acquisition mode' are revisiting their cashflow models and scrutinizing income streams far harder than would normally be the case, Savills said, adding that debt terms were now harder to obtain compared to the summer months.

Nervousness over the euro zone's debt troubles has caused investors to pare back an emerging interest in riskier secondary assets, a category in which many of the UK malls on sale fall into.

The average initial yield of the 16 malls traded in the third quarter was 8.4 percent versus 7.3 percent in the previous quarter, reflecting the riskier nature of the stock and investor nervousness about the market, Savills said.

Third quarter deal volumes reached 423.8 million pounds, which brought total volumes for the year to date to 2.9 billion pounds.

For the year to date, 40 malls have been traded, while 18 shopping centres are under offer, accounting for a total of 1.1 billion pounds. 28 other malls are up for sale for a total of 1.1 billion.

On the high street property market, Savills said there may be a rise in sales of bank-controlled or owned sites as more property investors ran into difficulty. It said a steady trickle could turn into a river.

(Reporting by Brenda Goh; Editing by Helen Massy-Beresford)