Timeline: Gulf of Mexico oil spill

(Reuters) - As the Gulf of Mexico oil spill dragged on, costs rose dramatically.

April 20, 2010 - Explosion and fire on BP's Deepwater Horizon drilling rig kills 11 workers. The rig, owned by Transocean Ltd and licensed to BP, was drilling 42 miles southeast of Venice, Louisiana, in 5,000 feet of water. The well had reached 13,000 feet under the seabed.

April 22 - The rig, valued at more than $560 million, sinks and a 5-mile (8-km) oil slick forms.

April 30 - BP CEO Tony Hayward says the company takes full responsibility and will pay all legitimate claims and the cost of the cleanup. Analysts say containment and cleanup costs could top $3 billion.

May 10 - BP says it has spent $350 million dealing with the leak. Analysts at Exane say it may have to take a $10 billion provision for the incident. Other analysts estimate the total cost between $5.1 billion and $8.2 billion.

May 11/12 - Executives from BP, Transocean and Halliburton appear at congressional hearings in Washington. The executives blame each other's companies.

June 9 - U.S. Interior Secretary Ken Salazar says BP must pay the salaries of thousands of workers laid off because of the moratorium on deep-sea drilling.

June 16 - Hayward and BP Chairman Carl-Henric Svanberg meet White House officials and announce a deal to set up a $20 billion fund for damage claims from the spill. BP also suspends dividend payments to shareholders; says it will pay $100 million to workers idled by the six-month drilling moratorium.

June 22 - Hayward hands day-to-day control of spill operations to managing director Bob Dudley, who had been CEO of BP's Russian joint venture, TNK-BP.

June 25 - BP says it has spent $2.35 billion on the response effort, including $126 million in claims to those affected by the disaster. July 19 - BP says it has spent $3.95 billion so far on efforts to tackle its well.

July 20 - BP says it has reached a deal to sell $7 billion in assets to Apache Corp as it raises money to cover costs related to the spill. It later says it plans to sell assets worth up to $30 billion over 18 months.

July 27 - BP names Bob Dudley as its next CEO.

August 2 - U.S. government data shows 4.9 million barrels of oil leaked before the well was capped.

September 16 - Relief well intercepts the Macondo well.

September 19 - With a final shot of cement, BP permanently "kills" the leaking well.

September 23 - Researchers put the spill at around 4.4 million barrels. The figure comes from the first independent study of the disaster.

September 26 - Halliburton, the oilfield services company that cemented the blown-out well, says a BP report laying the blame on the cement job offers a questionable account of events and "erroneous conclusions."

October 4 - BP says it is to raise 2 billion euros ($2.7 billion) via a bond issue to help finance its $20 billion compensation fund.

October 26 - The Gulf Coast Claims Facility, created to compensate people and businesses, says it has paid $1.55 billion in claims since it took over the process from BP on August 23.

November 2 - BP increases its estimate of the likely cost of its Gulf of Mexico oil spill to $40 billion from $32 billion.

November 9 - Shares in BP rise after a U.S. presidential panel says it found no evidence that BP deliberately chose to cut corners to save costs.

November 24 - Kenneth Feinberg, administrator of BP's fund for victims, encourages claimants to file early for final settlements to get the most generous terms.

-- The fund has made $2 billion in emergency payments to 125,000 claimants. The final amount is likely to reach $2.3 billion and compensate 175,000 individuals and businesses, Feinberg says. Around 400,000 claims have been filed.

(Writing by David Cutler, London Editorial Reference Unit;