Speechly Bircham has secured the latest in a string of major finance roles from specialist investment house Wharton Asset Management, with the firm acting on a $1.5bn (£800m) securitisation opposite sector leader Ashurst.

The deal, the fourth collateralised debt obligation (CDO) Speechlys has handled for Wharton in the past 12 months, saw Wharton issue four tranches of bonds through a special purpose vehicle to fund the $1.5bn acquisition of an asset-backed securities portfolio.

Finance partner Paul Kay led Speechlys' team on the deal, alongside tax partner James Carter.

Wharton, the high-profile fund manager founded by Maurice and Gabby Salem, has been a major client of Speechlys since first instructing the firm four years ago, with the law firm in September advising on the securitisation of a $7.3bn (£4bn) portfolio of loans.

Wharton, one of a handful of specialist investment houses to focus on managing asset-backed debt, currently has a $13bn (£6.9bn) portfolio of securities under management.

Kay told Legal Week: "We have acted on all of Wharton's securitisations in the CDO asset-backed securities market."

Arranger Calyon, meanwhile, instructed Ashurst finance partner Michael Smith, assisted by associate Dhanesh Sanichara, the third CDO instruction the firm has handled for the French bank in the last six months.

Ashurst has carved out an admired position in the European CDO market, predominately acting for underwriter clients like Deutsche Bank, Bear Sterns and JP Morgan, with Smith this month also signing off a £659.5m deal for Merrill Lynch ( see deal table, right).

Advisers are expecting the asset-backed securities sector to continue its robust growth this year, driven by demand for high-yielding investments from hedge funds and institutional investors, while creditors continue to use the market to take loans off balance sheet.

The sector is also regarded to have received an additional boost from the recent popularity of using credit derivatives like credit default swaps as trading products as opposed to hedging tools.