* Hang Seng Index pulls back from 28-month high
* Shanghai stocks slip; financials weaker after RRR rise
* Auto shares rally on strong monthly sales, results
* Short-covering seen in Tencent; shares rise 4.5 percent (Updates to midday)
By Vikram S.Subhedar and Farah Master
HONG KONG/SHANGHAI, Oct 12 (Reuters) - Shares in Shanghai and Hong Kong slipped on Tuesday morning from recent peaks as weakness in Chinese banks following a surprise temporary rise in reserve requirements weighed on the markets.
China's benchmark stock index had eased 0.3 percent by the midday break after a two-day climb, with gains in autos failing to offset mild profit-taking in banks.
The Shanghai Composite Index ended the morning at 2,799.2 after closing up 2.5 percent on Monday, its biggest two-day jump in more than 12 months.
Reuters reported on Monday after the close of Shanghai's market that China had raised reserve requirements for six large commercial banks on a temporary basis, in a surprise move to drain cash from the economy.
"In the short term there will be an impact on bank earnings and stock performance but the adjustment was within market expectations. The significance is more of a warning that the central bank is keeping an eye on rising liquidity," said Chen Xingyu, analyst at Phillip Securities in Shanghai.
Agricultural Bank of China Ltd was down 0.7 percent, Bank of China Ltd fell 1.5 percent and Industrial and Commercial Bank of China Ltd (ICBC) dropped 1 percent. All three are on the list of banks subject to the central bank's temporary lifting of reserves.
Auto shares surged on solid earnings results.
Top Chinese automaker SAIC Motor Corp Ltd gained 7.4 percent after saying it expected net profit for the first nine months of the year to grow by at least 140 percent from a year earlier.
Changchun Faway Automobile Components Co Ltd jumped 5.8 percent, while Huayu Automotive Systems Co Ltd rose 7.8 percent.
HONG KONG FALLS
Hong Kong's benchmark Hang Seng Index slipped as investors booked profit in large cap stocks, including banks, which had led the market to a 28-month high in recent sessions.
The Hang Seng Index fell 0.52 percent to 23,087.42. The China Enterprises Index was down 0.44 percent at 12,894.79.
A rebounding mainland market and strong foreign flows into regional markets has lifted the Hang Seng Index out of a trading range that had been in place since November 2009.
Speculation about another round of asset purchases by the U.S. Federal Reserve has grown after a weak jobs report on Friday, keeping the dollar weak and boosting flows into emerging market stocks and bonds and precious metals such as gold.
The Hang Seng Index's 12.5 percent run up in the past five weeks has take it into technically overbought territory, with its relative strength index at 81, the highest in more than three years.
"It looks like people are happy to add more risk heading into year-end. That's different from this time last year when they were basically trying to match their benchmarks," said the head of a trading desk at a bank in Hong Kong. "But I think with results season here, people will start to look at fundamentals a little more and given the run-up we've seen, earnings coming out of the U.S. now have to be pretty good."
Tencent Holdings Ltd jumped 4.5 percent with certain market players covering their short positions.
Short-selling in Tencent, as a percentage of total turnover in the stock, has outpaced that seen in the broader market. The five-day average shorted turnover in Tencent was 14.8 percent versus 5.4 percent for all Hong Kong stocks.
Declines in large cap stocks weighed on the market. CNOOC Ltd fell 2.5 percent and China Mobile eased 1 percent. ($1=6.671 Yuan) (Editing by Chris Lewis)