Saudi Arabian shares ended low, giving up modest early gains as concerns about US debt ratings downgrade still lingered on investor sentiment.Saudi\'s index slipped 0.3 percent ending at 6,058 points. The index slumped to a 5-month low on Saturday.Top lender Al Rajhi Bank dropped 1.1 percent while chemicals firm Saudi Basic Industries Corp ended flat.\"Roughly 90 percent of the activity is retail driven, with institutional playing little part,\" said Asim Bukhtiar, head of research at Riyadh Capital.\"The US session will be key to watch and see how Saudi reacts tomorrow.\" US stock index futures tracked a sharp drop in global equity markets on Monday after Standard & Poor\'s cut the top-tier AAA credit rating of the United States, rattling already-jittery investors.Dubai\'s index ended slightly lower, giving up modest earlier gains, but with improved sentiment as investors took the view that Sunday\'s sell-off may have been overdone.The benchmark eased 0.8 percent to 1,473 points. It sank to a 20-week closing low on Sunday on US and European debt worries.Emaar Properties fell 1.7 percent, Dubai Islamic Bank declined 3 percent and Aramex stumbled 2.8 percent. Heavyweight Emirates NBD rose 1.8 percent.Abu Dhabi property stocks gained, helping lift the index to a higher close, up 0.4 percent to 2,613 points. The benchmark rose from Sunday\'s 10-week low.Surouh Real Estate and Aldar Properties both ended up 0.8 percent. In Qatar, the index dropped 0.8 percent lower to close at 8,215 points. Oman\'s shares ended lower for a second-day, hampered by negative sentiment over the US credit rating downgrade, but appealing share valuations helped limit selling pressure. The benchmark closed 0.8 percent lower at 5,604 points, a fresh two-year low. \"Overall the risk reward ratio is turning positive with the market pricing in for most of the uncertainties,\" said Kanaga Sundar, Gulf Baader Capital Markets head of research. \"The market is going beyond fundamentals right now and is looking more at risk aversion. Already our market has underperformed for the current year and we may see institutions bottom-fishing for blue-chips,\" he added.The main drag was heavyweight Bank Muscat which fell 0.9 percent. Renaissance Services slipped 0.8 percent.Oman Telecommunication Co closed 1.7 percent higher, ahead of its second quarter results which are expected in coming days. From / Arabian Business News