The chief executive of the UK's biggest law firm DLA Piper, Simon Levine, has urged the legal market not to respond with panic following the British public's vote to leave the European Union (EU).

Speaking to Legal Week this morning, Levine said the legal industry "owes it to people who work in it, and clients, to have a period of calm and reflection" and it should "keep calm and carry on".

Several firms, including Clifford Chance and Linklaters, set up dedicated client hotlines or 'war rooms' this week to deal with any fallout from last night's vote. Partners at DLA Piper have been responding to client queries that have come in, but Levine questioned the approach of some of the firm's peers.

"We're here to advise but we're not going to turn this into a crisis. This morning, I wasn't going into the nuclear bunker at the bottom of my garden," he said.

"Without trying to be disrespectful, I can't imagine what they will be doing. Forensically, what exactly are they going to say? Other than the theory behind regulation and how things will go, there is nothing you can say – how can you possibly know?"

Levine does not expect the effect on international firms to be cataclysmic. He is confident that all jurisdictions will continue to be covered effectively when Britain leaves the EU.

"If we were to take an example, if we have a case that needs trying before the EU patent office in Germany, then one of our German patent partners will deal with it," he said.

He flagged the fact that much of the firm's work and revenue comes from outside of EU countries and will continue to do so unchanged by today's development.

"We work on an international basis with the US, China and Africa – none of these places are in the EU. I don't want to dismiss it as a non-event but I see no reason why it should have a cataclysmic effect on our business," he said.

He said, as several others have done in recent months, that an out vote will lead to a plethora of work for firms.

"It will present a lot of opportunities for most firms throughout Europe and the UK. There will be a lot of businesses thinking about what business they do and how they restructure themselves," he added.

However, he acknowledged that currency fluctuations will have an effect on all firms.

This morning, the pound dropped to its lowest level since 1985, as it became clear that Britain had voted out, having already collapsed a historic 13% against the Japanese yen, though it has since recovered some ground.

Levine said: "The currency is changing and that will change all businesses, including ours. You take steps to deal with that. We don't pay everyone in reference to sterling and we operate in number of different currencies. It's no great secret that all international businesses hedge and we've known there was a possibility of leaving the EU for some time, so you carry assurance against those fluctuations to a degree."

Following the referendum result, Prime Minister David Cameron pledged to resign by October this year, when the Conservative party will choose a new leader. He said it would be up to the new Prime Minister to carry out the negotiations over the UK's exit.

Levine commented: "Things are moving very quickly and clearly things will settle. None of this is going to happen before you have a new government and we could be looking at another couple of years of discussions. The legal industry owes it to people who work in it, and clients, to have a period of calm and reflection."