When Paul Weiss Rifkind Wharton & Garrison hired Simpson Thacher & Bartlett corporate partner Alvaro Membrillera earlier this year, the move marked the elite US firm's first lateral hire in London since it first opened in the City 16 years ago.

Given the firm's London base had been led by the same two partners – Mark Bergman and David Lakhdhir – ever since its 2001 launch, it is fair to say the hire came as a surprise to many.

Speaking to Legal Week, firmwide chairman Brad Karp is understated when he describes the firm as "extremely selective" when considering lateral hires. "We were looking for someone spectacular – someone who 'walked on water'," he says.

In total, the firm spent five years searching, on and off, for the right partner before settling on Membrillera, who advises buyout houses including KKR, which he will continue to work with at Paul Weiss.

Karp explains: "We had been in the market quite a while looking for a superstar, US-qualified, private equity M&A lawyer in London.

"Mark and David will absolutely remain as senior partners in our London office. With Alvaro's hiring, our team has become larger and younger – I certainly hope Alvaro will make Paul Weiss his home for the remainder of his career."

But while the prospect of a move to a firm posting profits per equity partner (PEP) of $4.38m (£3.47m) for 2016 may be of interest to many of the City's top corporate talent, potential recruits should not hold their breath. According to Karp, while the office will continue to grow lower down the ranks, the firm is no longer in the market for new lateral partner hires.

With Membrillera, who was made up to partner at Simpson Thacher in 2011, the City base will have three partners, alongside four counsel and 15 associates.

Karp insists the firm has no intention of moving into UK law advice. "We expect to remain a US-law practice. We have no plans to hire UK-qualified lawyers," he says, adding that other offices in Europe are also not on the agenda for Paul Weiss,  which counts London as its sole European base.

However, while Karp is circumspect about expansion, he concedes the firm is open to moves into new practice areas in London. Currently, its City base focuses on private equity and M&A, but Karp says it would consider adding its global areas of strength – litigation, regulatory defence and restructuring – to London, if the right person came along.

Karp comments:  "Right now, we are focused principally on private equity and cross-border M&A deals [in London]. We are always open to considering other practice areas that make sense strategically for the firm and tie into the firm's overall strategy."

He adds: "We've been fortunate in that several of our most significant private equity clients have looked to our London team to service their cross-border M&A deals. I would expect that trend to continue."

Paul Weiss's core private equity clients in London include New York-headquartered groups Apollo Global Management and General Atlantic, as well as Los Angeles-headquartered Oaktree Capital Management.

With the firm openminded about looking beyond its core transactional practices, has Brexit given it any cause for concern? Karp says the firm is reviewing the effects of the UK's departure from the EU on its cross-border M&A practice.

He comments: "Obviously, Brexit was an eye opener for us as it was for the global legal community, and we are continuing to closely monitor its effects. So far, Brexit has not had any discernible effect on our cross-border M&A practice. We remain optimistic based on our dealflow over the past year."