Linklaters has picked up its second Herbert Smith Freehills financial regulatory partner in under six months, with the magic circle firm set to bring in Nikunj Kiri as a partner.

His hire comes after Legal Week reported in September that Linklaters had hired contentious regulatory heavyweight Martyn Hopper to boost its City practice.

Hopper, who prior to joining Herbert Smith was head of the market integrity group in the enforcement division of the Financial Services Authority (FSA), is still serving out his notice period but is thought to be joining Linklaters within the next few months.

Kiri joined Herbert Smith as a trainee in 2001, and made partner in 2010. During his time at the firm he represented UBS as an interested party in the FSA's unsuccessful enforcement action against former UBS executive John Pottage, a landmark test case on the regulatory responsibilities of senior management at large financial institutions.

It is not clear when he will join Linklaters but Herbert Smith has been known to hold partners to close to their full notice periods. The former head of its investigations and corporate crime unit, Peter Burrell, was held to 11 months' notice after agreeing to join Willkie Farr & Gallagher in 2011 for example.

The firm recently cut its notice period back from 12 months to six as a result of the tie-up with Australia's Freehills, which went live in October.

It is understood the legacy Herbert Smith could still try to enforce a one-year notice period on partners who quit before the change was implemented. This could potentially include senior litigation partner Kevin Lloyd, who is set to join Debevoise & Plimpton, and corporate partner Will Pearce, who is departing for Davis Polk & Wardwell.

Both Linklaters and Herbert Smith declined to comment on Kiri's appointment.