Moody's Investors Service on Tuesday downgraded the long-term deposit ratings of Bank Muscat (to Baa1 from A3), Oman Arab Bank (to Baa2 from Baa1) and Bank Dhofar (to Baa2 from Baa1) and confirmed the Baa1 long-term deposit rating of HSBC Bank Oman. The ratings agency assigned a negative outlook to Bank Dhofar's long-term ratings while the ratings of the three other banks have a stable outlook. The rating actions follow Moody's downgrade of Oman's government issuer rating on Saturday to Baa1 from A3, the rating agency said in a statement. (Muscat daily)   Bank Muscat: OMR0.402 as of 17 May, Rating: Buy, FV: OMR0.490/share, MCap: USD2,546mn, BKMB OM / BMAO.OM