The UK Treasury and UK Government Investments Limited (UKGI) have undertaken to the bookrunners of the latest sale of shares in NatWest-RBS “not to sell further ordinary shares of the company for a period of 90 calendar days … without the prior written consent of a majority (by participation) of the bookrunners.”

The undertaking came with confirmation that the Treasury sold another 5% of the banking group — 580 million shares — at 190p per share to institutional investors to raise £1.1 billion.

This is the UK government’s fourth sale of its NatWest shareholding and its second transaction in two months as it continues its sell-down of the UK taxpayer’s majority shareholding in the bank formerly known as RBS.

The process was managed by UK Government Investments.

The Treasury has now reduced its shareholding in NatWest-RBS from 59.8% to 54.8%.

UKGI said: “Subject to certain exceptions, UKGI and HM Treasury have undertaken to the bookrunners … not to sell further ordinary shares of the company for a period of 90 calendar days following the completion of the placing without the prior written consent of a majority (by participation) of the bookrunners …

“Barclays Bank PLC, Citigroup Global Markets Limited, Goldman Sachs International and Morgan Stanley & Co. International plc acted as joint bookrunners in connection with the placing.

“N.M. Rothschild & Sons Limited acted as Capital Markets Adviser to UKGI on the placing.

“Freshfields Bruckhaus Deringer LLP acted as legal counsel to UKGI in respect of English and US law.”

The Treasury said: “This is the government’s fourth sale of its NatWest shareholding, and its second transaction in two months, bringing its level of ownership down from 59.8% to 54.8%.

“This sale represents further progress in the government’s plan to return institutions brought into public ownership as a result of the 2007-2008 financial crisis to private ownership.

“The sale was completed by way of an overnight sale via an accelerated bookbuild, a competitive market facing process that involves selling shares to institutional investors.

“The government continues to keep all options and timings under review for future sales.”