LONDON • After more than a year of marathon restructuring negotiations, Noble Group looked to be entering the home stretch.

The debt deal, which chairman Paul Brough described as "probably the most complex restructuring ever undertaken in Asia", had run the gauntlet of all-night negotiations and court hearings. It was due to complete in less than a week.

Now the US$3.5 billion (S$4.8 billion) restructuring hangs in the balance after the Singapore authorities announced on Tuesday a multi-agency investigation into the commodity trader.

Should the deal fail, it would be a blow to Noble's creditors, including hedge funds Taconic Capital Advisors, Varde Partners and Owl Creek Asset Management, as well as Deutsche Bank and ING Group.

Noble Group said yesterday it will continue to work towards implementing its proposed restructuring within the previously disclosed timelines and it is in the best interest of all shareholders and creditors.

The announcement of the probe came as a surprise to the company's creditors and advisers, according to three people working on the deal, who asked not to be named. They had been racing to complete the restructuring ahead of a deadline, the so-called "long-stop date" of Nov 27. According to an announcement last week, the deal was due to be completed next Monday.

CAN THE PROBE DELAY NOBLE'S RESTRUCTURING?

The Singaporean regulators on Tuesday suggested the probe could delay the restructuring deal. "Trading can only start after restructuring has been completed and this is in turn dependent on our review," said SGX RegCo, the regulatory arm of the Singapore Exchange.

In a circular to shareholders published in August, one of the conditions without which the restructuring cannot go ahead is for the SGX to give consent for the restructured entity to be relisted.

Another "conditions precedent" is for the Securities Industry Council and the Monetary Authority of Singapore to grant waivers needed so that the restructuring can go through without Noble's creditors being forced to make a buyout offer for its shares.

DOES A DELAY MATTER?

The long-stop date for the Noble restructuring is Nov 27, according to a copy of its English scheme of arrangement. That means that if the restructuring has not been completed by then, the schemes of arrangement - by which Noble is implementing its debt restructuring - "shall be of no effect".

Still, the scheme of arrangement provides that the date can be pushed back to any day until Dec 31, with the agreement of Noble and its creditors.

A bigger problem may be that Nov 27 is the day on which a key waiver expires. Granted by Noble's shareholders in August, the waiver allows the deal to go ahead without Noble's creditors being forced to make a buyout offer for its shares.

In its circular to shareholders, Noble said that Singapore's Securities Industry Council had allowed it to go ahead with the restructuring without a buyout offer being made, as long as the deal was completed within three months of the approval of the whitewash resolution.

WHAT MIGHT NOBLE AND ITS CREDITORS DO NOW?

Noble and its creditors will contact the Singapore authorities to work out if there is anything they can do to persuade the regulators to approve the deal ahead of the Nov 27 deadline, the people familiar with the matter said.

That could involve, for example, agreeing that the restructured Noble Group would guarantee to pay any fine that arises from the Singapore investigation.

However, at the moment it is not clear what the authorities require to wrap up the restructuring.

WHAT HAPPENS IF THERE'S NO RESOLUTION?

Noble and its creditors have repeatedly stated that the only alternative to the restructuring plan is to file for insolvency.

Under an "alternative restructuring" plan set out in Noble's shareholder circular, the company would file for administration in Britain. The creditors would take control of the company, and shareholders and perpetual bond holders would likely be wiped out.

Still, Singapore would still have significant sway over what remains of Noble.

One of the entities it is investigating is Noble Resources International (NRI), its main operating subsidiary, based in the Republic, and the unit through which it carries out much of its trading activity.

Noble Group said the company and NRI intend to cooperate fully with the authorities in their investigation.