* Provision also for potential resolution of U.S. investigations
* Also covers $133 mln British fine over financial crime controls
* StanChart's Hong Kong shares trade flat after initial dip (Updates Hong Kong share price, adds London trading activity)
By Alun John and Sumeet Chatterjee
Feb 21 (Reuters) - Standard Chartered PLC (StanChart) has set aside $900 million to cover fines resulting from regulatory investigations in the United States and Britain, potentially drawing a line under probes which have dogged the bank for years.
News of the provision, made for the fourth quarter of last year, comes ahead of a strategy update from the bank along with its 2018 earnings results on Tuesday, when Chief Executive Bill Winters is widely expected to outline an overhaul of operations.
In a filing to the Hong Kong Stock Exchange on Thursday, StanChart said the provision related to the potential resolution of U.S. investigations into alleged violations of U.S. sanctions, and for probes relating to foreign exchange trading.
The filing is the first time the bank has quantified the possible cost of the investigations. Previously it said only in filings that it was "not practicable" to estimate the financial impact because the range of potential outcomes was too broad.
StanChart also included in the provision a 102.2 million pound ($133.3 million) fine from Britain's Financial Conduct Authority related to historical financial crime controls. It said it was considering its options in relation to the penalty.
The British regulator declined to comment when contacted by Reuters.
StanChart has been the subject of multiple investigations by U.S. authorities into its dealings with Iran, which is the subject of heavy U.S. sanctions.
In 2012, the bank agreed to pay $667 million to settle alleged sanctions breaches from 2001 through 2007. It also agreed deferred prosecution agreements with the Department of Justice and New York County District Attorney's Office. The agreements were extended to March 31 this year in December 2018.
The current investigations are examining the extent to which the bank allowed clients with Iranian interests to conduct transactions after 2007, as well as the extent to which it shared such dealings with authorities at the time of the 2012 settlement.
In October, Winters said U.S. authorities were also investigating whether StanChart breached Iran-related compliance rules as recently as 2013.
Media reports last year said London-based StanChart faced a possible $1.5 billion fine for Iran-related sanctions violations.
The 2018 provision will reduce profit at the bank, which analyst estimates had previously put at $3.9 billion, Refinitiv data showed.
"The provision is huge and unexpected," said Steven Leung, a sales director at brokerage UOB Kay Hian. However, the impact on StanChart stock might be limited if the profit hit meant future earnings could be flattered by the low comparison with 2018, Leung said.
In the first hour of London trade, shares in the bank were up 1.7 percent compared with a 0.5 percent fall in the blue-chip FTSE 100 index. In Hong Kong, shares of StanChart closed 0.6 percent lower.
"Though the provision amount is not small, it removes some of the uncertainties related to past issues," said Hao Hong, brokerage BOCOM International's head of research.
Last month, New York's financial watchdog fined StanChart $40 million for attempting to rig foreign exchange transactions from 2007 through 2013 - a penalty which the bank said was also included in the $900 million provision.
Asia, Africa and Middle-East focused StanChart has seen a slump in fortunes over the past few years as restructuring under Winters repaired a balance sheet hit by excessive lending in the previous decade, but left the bank struggling to lift profit.
StanChart has projected revenue growth of 5 to 7 percent over the next three years, but Jefferies analysts in a report this week said a consensus of analyst estimates was "anchored at the lower end" of the guidance, adding that even this "looked challenging".
StanChart's London shares fell 22 percent last year, compared with the 15.6 percent drop at rival HSBC Holdings PLC .
($1 = 0.7665 pounds)
Reporting by Alun John and Sumeet Chatterjee in HONG KONG and Nikhil Kurian Nainan in BENGALURU; Additional reporting by Donny Kwok in HONG KONG and Aditya Soni in BENGALURU; Editing by Richard Pullin and Christopher Cushing