BP has pledged $500 million to study the impact that its massive oil spill is having on the Gulf of Mexico. The oil company says the money will go toward funding a 10-year research effort aimed at looking into the long-term effects the spill is having on the Gulf.

A BP spokesman said Monday that the amount of oil it is diverting from the Gulf of Mexico floor has declined to 1,120 barrels a day.

Top U.S. officials are assessing the company's response to the spill. BP is under fire for not being able to stop the spill and its inability to estimate how much oil it is siphoning from its ruptured well.

From Reuters:

BP said on Monday the oil collected by the mile-long siphon tube was at times as low as 1,360 barrels of oil per day in the six days to May 23 with the tube capturing an average 2,010 barrels per day in the time period. The average figure is less than half the 5,000 barrels per day the company estimates is leaking into the sea and comes after it said it was managing to siphon off around 5,000 barrels per day a few days ago. Some experts have given significantly higher estimates for the size of the leak. BP said the spill which has seen oil flowing into the sea for more than a month after a rig explosion in April had cost it $760 million so far, up from the $625 million estimate it reported on May 18.

The U.S. government has repeatedly threatened to take over clean-up and response efforts.

Follow our coverage of the spill here.

Follow Daryl Paranada at @darylparanada