UPDATE 2-SP Ausnet scraps Alinta asset buy, shares jump

(Adds analyst comment, shares, byline)

By Ben Wilson

SYDNEY, Dec 10 (Reuters) - Australian infrastructure firm SP Ausnet SPN.AX SPAU.SI pulled out of a plan to pay A$8.3 billion ($7.3 billion) for assets of former energy firm Alinta, blaming a downturn in capital markets, sending its shares up 9 percent on Monday.

SP Ausnet had planned to buy the east coast power line and gas pipeline networks from its state-owned parent Singapore Power, which bought them in August, but called off a shareholder vote on the deal due on Tuesday.

It said the ongoing deterioration in capital markets would have had a material impact on the proposed deal, including its ability to hit forecasts.

"In more normalised markets maybe this deal did make sense," said Andrew Chambers, infrastructure analyst at Austock.

"Our simple message is: Singapore Power paid top of the market for these assets, and SP Ausnet were going to buy them at top of the market prices, but issuing equity and debt at bottom of the market levels."

SP Ausnet shares shares, which had fallen nearly a fifth this financial year, jumped as much as 9.2 percent, and traded 7.1 percent higher at A$1.28 by 0210 GMT.

A succesful acquisition would have transformed SP Ausnet into Australia's largest energy transmission company, but the deal had attracted criticism from analysts because of its size and cost.