UK – Universities Superannuation Scheme has named Bill Galvin, the current head at the UK Pensions Regulator, as its new chief executive.

The country's second-largest fund – with £32bn (€39bn) in assets – said Galvin would join in August, replacing retiring group chief executive Tom Merchant.

The regulator said it would begin to look for Galvin's replacement shortly and announce the appointment "as soon as practicable".

In the interim, Galvin will hand responsibility for all matters relating to defined benefit (DB) regulation to TPR chairman Michael O'Higgins and Stephen Soper, executive director for DB, to avoid any conflict of interest with his new role.

As a result, he will also avoid dealing with the regulator until October.

Galvin said leaving the regulator after five years would be "very hard".

"I leave behind a hugely capable and committed team, which has a clear vision on how to support this vital industry," he said.

Of his appointment as group chief executive at the fund, he added: "I'm joining USS at a time that, for pensions, is both exciting and challenging.

"The task of supporting the USS trustee board in meeting the current and future expectations of scheme members, employers and other stakeholders is one of considerable responsibility, and I am looking forward to leading the team."

Pensions minister Steve Webb said he had enjoyed working with Galvin "at a time of major reform" in the UK pension landscape.

"As the Pensions Regulator's chief executive, he helped lay the groundwork for the introduction of automatic enrolment.

"He has worked with the industry on new standards for defined contribution pensions, as well as [sought] to ensure the proper regulation of company pension schemes."

O'Higgins added that he was "very sorry" to see Galvin leave, but said: "Following his successful internal reorganisation of the regulator around its three key tasks – defined benefit, defined contribution and automatic enrolment – he leaves us well prepared for our growing remit."

The president of the Society of Pension Consultants, Roger Mattingly, meanwhile said that Galvin's contribution to the pension industry had been "immeasurable". Of his replacement, Mattingly said that he would not have much time to adjust to the role. "The new appointment will need to hit the ground sprinting at full tilt rather than simply running."

Galvin joined TPR in late 2008 and was named acting chief executive in May 2010, following the departure of Tony Hobman.

He was officially named the regulator's head in January 2011 and has previously worked at the Department for Work & Pensions, where he was responsible for pension protection strategy, at as a consultant for IBM.

The chairman of the USS trustee board, Martin Harris, said he was delighted by the new appointment, only the fourth group chief executive in the fund's nearly 40-year existence.

However, he said he wanted to express his "warmest thanks" to Merchant as he retired.

"He has led the company through the last decade with considerable skill and judgement, and the board extends its very best wishes as he prepares for his retirement from the company at the beginning of May," he said.