The steeply listing 40-story platform was stable on Sunday after sinking more than 13 feet (four metres) since explosions ripped through a column and threatened to send the rig to the bottom of the ocean, Brazil's state oil giant Petrobras said.

"It's not sinking any more, it stopped late last night for the first time since the explosions," a Petrobras spokesman said.

Petrobras stepped up efforts this weekend to save the rig, flying in US and Dutch experts and 50 tonne of European equipment to keep the deep-sea platform afloat and prevent an oil spill. Three blasts rocked the rig early Thursday, killing 10 ofthe 175 men aboard and seriously injuring another.

Petrobras said on Saturday that it had given up hope that nine missing workers from the rig's fire brigade had survived, and counted them among the dead.

Petrobras, the biggest company in Brazil, said it was still trying to determine the cause of the explosions, which local media has attributed to a natural gas leak.

With close to 350 engineers, divers and navy men working around the clock, Petrobras started to right the platform on Sunday, though it was still keeled over more than twice as much as the Leaning Tower of Pisa. Only five men at a time are allowed to stay on the platform, Petrobras said, and support boats have been ordered to keep a distance of 555 yards (500 metres) from the rig.

The recovery of the bodies of the dead was "the main task", according to Petrobras president Henri Philippe Reichstul.

Only one severely burned body that had been hanging from a support column was recovered. After an autopsy and DNA tests, Petrobras said on Sunday that it had identified the 34-year-old father of one son. The others are presumed to be in a chamber that was completely submerged.

In Macae, the gateway to the oil-rich Campos Basin off the coast of Rio de Janeiro state, grieving relatives were in hotels hoping at least to take home the bodies of the dead workers. A team of 40, including 11 Dutch platform-rescue specialists, were injecting compressed air and nitrogen into the submerged column and sucking out the ocean water in a bid to right the platform and prevent an environmental disaster. If the rig were to sink, up to 395,000 gallons (1.5 million litres) of crude and diesel in underwater pipelines and onboard tanks could be dumped into the ocean.

Environmentalists worry the slick could head toward precious mangroves along the Rio coast, but Petrobras says it has sent boats to suck up any spill and has placed floating absorption barriers around the rig to prevent a slick from spreading.

Federal environmental agency IBAMA said calm seas and north-easterly winds were likely to take any unrecovered oil out to sea. If it did float toward land, it would take eight days to reach the beaches. Petrobras ruled out the chances that any of the 21 wellheads could break, which would have led to a much more serious environmental disaster. Petrobras has been struggling to rebuild its reputation after two major oil spills and a series of accidents, in which 81 workers died in the last three years.

The accident is a fresh blow to Petrobras, which has been trying to establish a reputation as one of the world's leading oil companies. The firm is already considered a global expert on deepwater production. The P-36 rig was supposed to be the prime example of Petrobras' deepwater expertise. It is located in the Roncador oilfield 78 miles (125 km) off the Rio coast in the Campos Basin, which produces 80 per cent of Brazil's oil. After starting operations last year, it was only pumping out 80,000 barrels of oil per day - about 5 per cent of Brazil's total output.

(Reuters)