The Royal Bank of Scotland (RBS) has delayed sending out tender documents for its UK legal panel as the bank looks set to push back a review that is expected to slim down its nearly 60-strong roster.

It is understood that the bank had planned to kick off the review process in the first quarter of this year with a submission deadline pencilled for the end of June, but now it may not contact firms until after the summer or as late as early next year.

The three-year term of the current panel is due to expire on 1 January 2016.

Factors that are believed to have affected the timing of the tender process include the appointment of a new chief legal officer at RBS in January; the bank's decision to roll back its international presence; and a high volume of litigation and regulatory work in recent months.

The tender race is also understood to be being run from the bank's office in Scotland, whereas previous reviews were run from the City.

A partner at one of the firms on the panel said: "I suspect because they've just got so much going on it was easier to kick that [panel review] into the long grass."

Firms appointed to the roster in 2012 include Linklaters, Clifford Chance, Allen & Overy, Herbert Smith Freehills, Simmons & Simmons, Ashurst, Eversheds, Travers Smith, Watson Farley & Williams, legacy Squire Sanders and Stephenson Harwood.

A RBS spokesperson said the bank was still on track to appoint the new panel effective from 1 January 2016.

RBS rival Lloyds Banking Group recently backdated the appointments to its legal sub panels as a means of maintaining the panels' regular review schedule despite announcing the line-up later than expected.