It’s not every day you meet a former United States president down the gym. But that’s exactly what happened one lucky Irishman who bumped into Barack Obama in California last week.

County Clare man Peter Barron was staying and working out in St Regis Hotel in San Francisco when he spotted someone with a strong resemblance to the two-term president.

Read More: This Irish song is one of Barack Obama's official favorites of 2018

Initially, he didn’t believe his own eyes and let Obama leave without making any contact.

Former US President Barack Obama in Moneygall, Co. Offaly, 2011. Image: Getty

Former US President Barack Obama in Moneygall, Co. Offaly, 2011. Image: Getty

However, later that night Barron saw John Legend emerge from a blacked-out car and realized some A-listers may be residing at the hotel so he made a few inquiries.

Through a friend, he heard Obama was, in fact, staying in the same hotel so when he spotted him in the gym for a second time Barron made no mistake in introducing himself.

Read More: Barack and Michelle Obama statue unveiled in Moneygall, County Offaly

Speaking on "Today FM's Dermot and Dave Show," fitness professional Barron revealed meeting the ex-president left him starstruck.

Peter Barron met former US President Barack Obama in a California gym last week. Image: Instagram

Peter Barron met former US President Barack Obama in a California gym last week. Image: Instagram

"I kind of panicked a bit and just said you did a great job with the Barack Obama Plaza,” he said.

Obama famously visited the small Offaly village of Moneygall in 2011 after discovering his third great grandfather Falmouth Kearney, emigrated from Ireland to the US in 1850.

In 2014 an $8 million (€7 million) service station was opened on the outskirts of the village and named in Obama’s honor.

Barron told Obama he was from "just over the road" in County Clare, prompting Obama to joke that they were family. 

Obama then went back to his work out but not before the former president remarked, "send all my love back to Ireland." 

Read more: Former First Lady Michelle Obama’s Irish slave owner roots

Barron did ask him for a picture but Obama declined to say, "if I give you a picture, everyone will want one." 

What do you think about this chance encounter with Barack Obama? Have you ever met the ex-president? Let us know in the comments below.