Weil Gotshal & Magnes and Clifford Chance (CC) are to go head to head in a $6.5bn (£4.6bn) arbitration case, over a financing agreement provided to a development company owned by the Malaysian government.

The providers of the financing – International Petroleum Investment Company (IPIC) and Aabar Investments PJS – claim that Minister of Finance Inc., Malaysia (MOF) and 1Malaysia Development Berhad (1MDB), a company owned by the Malaysian government, have defaulted on the terms of the financing agreement and owe billions of dollars.

Today (17 June), the financiers announced they would seek to claim $6.5bn in the London Court of International Arbitration.

CC is representing long-term client IPIC and Aabar, with a team led by Audley Sheppard QC and litigation partner Roger Best.

Weil is advising 1MDB, with a London-based team including dispute resolution partner Jamie Maples, restructuring partner Mark Lawford and City restructuring head Adam Plainer.

1MDB said in a statement that it will file "a robust response" to the arbitration request before the deadline of 11 July.

Weil partner Maples is also currently advising online retail department store Littlewoods on its £1.2bn claim in a long-running dispute with HMRC concerning interest on overpaid VAT. The judgment was upheld by the Court of Appeal last year and the case is due to be heard by the Supreme Court in July 2017.

Lawford, who made partner at Weil in 2013, previously advised Lehman Brothers Holdings on its insolvency process, including the sale of subordinated debt in Lehman Brothers International.