Challenger banks in the U.K. have written to the central bank seeking softer rules to allow them to better compete with bigger rivals, banking industry sources told Reuters.

The banks have reportedly been holding meetings with the Bank of England and the finance ministry in recent months, asking the central bank to lower the minimum requirement for own funds and eligible liabilities for banks with assets of £12 billion to £15 billion, according to the report. They sought a "glide path" to make requirements easier to meet, the sources said.

The banks have also lobbied for the Treasury to reduce their regulatory responsibilities in an ongoing review.

Among the challenger banks in Britain are Virgin Money UK PLC, TSB Banking Group PLC, Metro Bank PLC, Co-operative Bank PLC, Secure Trust Bank PLC and Monzo Bank Ltd.

However, the request to lower requirements could be shunned by regulators following recent issues faced by challenger banks, particularly Metro Bank's accounting blunder and the IT problems dogging TSB, Reuters noted.