LONDON, March 28 (Reuters) - Liberty Steel, owned by commodities tycoon Sanjeev Gupta, has reached an agreement with major creditors after raising capital, paving the way for a restructuring of its British business, it said on Thursday.

Liberty is part of Gupta's family conglomerate, GFG Alliance, which has been refinancing its businesses in steel, aluminium and energy after its backer, supply chain finance firm Greensill, filed for insolvency in March 2021.

The capital increase includes a $350 million bond issue by one of its Australian units through Jefferies and a $350 million asset-backed term loan from BlackRock and Silver Point Finance, a statement said.

The creditor agreement, which mainly involves debt of its British businesses, will allow Liberty to consolidate its British steel business under a new entity and corporate structure.

As part of the plan, Liberty, which has nine sites in Britain, plans to double melting capacity at its Rotherham plant in northern England to 2 million metric tons a year.

In January last year, Liberty suspended operations at two British plants and cut output at Rotherham due to high power prices.

Liberty also has operations in Europe, Australia and the United States.

Its Czech business Liberty Ostrava had said it would restart its blast furnace in January and increase production.

In 2021, Britain's Serious Fraud Office opened an investigation into alleged fraud, fraudulent trading and money laundering at GFG Alliance.

The company had consistently rejected any wrongdoing and pledged full cooperation. (Reporting by Eric Onstad. Editing by Jane Merriman)