Factbox: Developments in the Gulf of Mexico oil spill

(Reuters) - Here are some developments in BP Plc's Gulf of Mexico oil spill, the largest in U.S. history.

TOP DEVELOPMENTS

* BP Plc prepared to test a new cap installed on its runaway well in the Gulf of Mexico with hopes of finally arresting the flow feeding the worst U.S. oil spill.

* Regardless of the tests' outcome, the top U.S. official overseeing response to the Macondo well blowout said BP should be able to capture virtually all oil flowing from the well.

* Meanwhile, BP was moving ahead with plans to sell off assets and attract investment to withstand massive costs associated with the Gulf well disaster. Among assets being sold was storage at Cushing, Oklahoma.

CAPTURE/CONTAINMENT/CLEANUP

* BP's pressure tests on Tuesday were to determine whether it can use the new cap to simply shut in the well or will have to go to a fallback spill collection plan pending completion of relief wells.

POLITICS/POLICY

* The Obama administration's new moratorium on offshore drilling was seen as little changed from the one struck down by a New Orleans federal judge. It has a November 30 expiration date and talks of an earlier end if safety is assured.

* Gulf Coast officials urge Obama commission on oil spill to recommend easing drilling moratorium.

MARKET IMPACT/COMPANIES

* BP shares were up 2.86 percent in London Tuesday and closed marginally higher in New York after a see-saw session that saw early gains reversed by profit-taking.

* Florida banks are seeking capital-requirement waivers because of the oil spill's impact on business in the state.

* Magellan Midstream Partners to buy BP Plc storage at Cushing, Oklahoma, delivery point for U.S. crude futures for $289 million.

ENVIRONMENTAL IMPACT

* Unlike BP's spill, natural oil seeps can help sea life, scientists said. Such seeps account for about 45 percent of oil entering the oceans in a typical year. Microbes feed on oil and gas.

(Reporting by Bruce Nichols; Editing by Jerry Norton)