London Stock Exchange Group Plc's clearing arm LCH Ltd. plans to increase the eligibility of Sterling Overnight Index Average, or SONIA, interest rate swaps to 51 years before the end of the year, in a move to ease the transition from the existing, scandal-ridden London Interbank Offered Rate, Reuters reported.

The Bank of England's SONIA is set to replace LIBOR, which has been at the center of rigging scandals, as a benchmark for sterling-denominated derivatives and relevant financial contracts.

Increasing SONIA's range to clear the kind of long-dated swaps covered by LIBOR is one of the hurdles — along with the need for a dedicated clearing house offering over-the-counter SONIA swaps — in the transition, scheduled to be completed by 2021-end the newswire said.

"[The transition] may be difficult, it may happen on a different time frame depending on different levels of difficulty, but it will happen," said Francois Jourdain, chairman of the Bank of England-appointed Sterling Risk Free Rate Working Group and head of compliance at Barclays International.