Hundreds of miles of booms are being laid along the coastline
BP officials desperate to stem a huge oil spill in the Gulf of Mexico are considering stuffing the well with golf balls and tyres, it was revealed.
BP Chief Operating Officer Doug Suttles said the so-called "junk shot" of debris was one option after previous attempts to stem the flow failed.
A growing slick from the BP-leased rig is threatening an environmental disaster along US coasts.
Some 5,000 barrels (210,000 gallons) of oil a day are flowing into the sea.
Mr Suttles said it may be possible to stem the flow by blocking the well's failed blowout preventer.
"We have some pipe work on the blowout preventer, and if we can open certain valves on that we could inject basically just rubber and other type of material into [it] to plug it up, not much different to the way you might plug up a toilet," he said.
Admiral Thad Allen of the US Coast Guard said it could plug the main leak.
"They're going to take a bunch of debris, shredded up tyres, golf balls and things like that, and under very high pressure shoot it into the preventer itself and see if they can clog it up and stop the leak," he told CBS television.
ATTEMPTS TO CONTROL SLICK
Booms have been partly successful although rough seas have washed oil over them
Some controlled burning of oil has taken place, but it causes serious air pollution
About 325,000 gallons of dispersant have been used, although scientists warn it may kill marine life
A relief well is being drilled but could take many weeks
A huge steel funnel suffered a build-up of ice-like crystals and had to be put aside
However, experts have warned that any further damage to the blowout preventer - a huge valve system meant to turn the oil off - could see it shooting out at 12 times the current rate.
In other developments, a BP official told the Associated Press news agency on Monday that the company had received US government approval to continuously pump dispersant chemicals underwater.
BP spokesman Mark Proegler said engineers began pumping dispersant on the site on Monday morning.
Thousands of gallons of dispersant have been dropped over oil on the surface, but have not been tried at such depths before.
Scientists and fishermen have expressed concern that the chemicals could kill marine life.
BP revealed on Monday that the oil spill had cost the company $350m (£233m) so far.
It did not speculate on the final bill, which many analysts expect to run into tens of billions of dollars.
The Deepwater Horizon rig caught fire and sank following an explosion last month.
The resulting slick has so far thwarted all efforts by BP and US officials to bring it under control.
A 98-tonne concrete-and-steel funnel lowered 5,000ft (1,500m) to the seabed had been BP's best hope to contain the main leak while it tried to stop it altogether by drilling relief wells nearby.
But a build-up of gas hydrates - crystalline water-based solids resembling ice - inside the funnel blocked the exit at the top, and it had to be put aside on Saturday.
Mr Suttles said other options being discussed were to make a smaller containment dome or to tap into the broken riser pipe and take the oil directly to the surface.
The broken pipe is almost a mile (1.6 km) down on the ocean floor with little visibility for engineers using remotely controlled vehicles.
Although the Deepwater Horizon was operated by Transocean, BP is responsible for the clean-up.
Wildlife in the Gulf of Mexico is already suffering
The slick has so far covered about 2,000 sq miles (5,200 sq km).
US President Barack Obama is due to meet senior officials at the White House on Monday to review BP's efforts.
A sheen from the edge of the slick is surrounding island nature reserves off Louisiana and tar balls have reached as far as the Alabama coast.
The low-lying region contains vital spawning grounds for fish, shrimp and crabs and is an important migratory stop for many species of rare birds.
Louisiana's fishing industry has ground to a halt in certain areas due to health concerns about polluted fish.
Booms and bundles of absorbent material have been laid along shorelines to try to protect them.
Teams are also filling sandbags which the Louisiana National Guard will airlift on Monday to five spots along a threatened stretch of coastline.
The first two oiled birds rescued from the spill have been cleaned and were due to be released back into the wild later in the day.
The birds - a gannet and a pelican - were to be freed at Pelican Island National Wildlife Refuge in Florida.