The day began with a mildly offensive Irish cliché in front of a room-full of Irish people, and it all went downhill from there.

"Top of the morning," said Vice President Mike Pence, as he hosted Irish Prime Minister Enda Kenny at his residence for breakfast Thursday.

Really? The reaction by Irish on social media was palpable.

"Literally just shouted 'NOBODY SAYS THAT' at the TV," a journalist in Ireland tweeted. "I've literally only ever heard that said by Americans," another person said.

"How do all the Irish people not just go, 'nope,' and leave the room?" tweeted another.

Ireland's leader was in Washington for a series of events in celebration of St. Patrick's Day, including breakfast with the vice president, a luncheon at the U.S. Capitol, a one-on-one meeting with President Donald Trump and an long-standing annual ceremony in which the U.S. president is presented with a bowl of shamrocks.

Long before the festivities began, the visit was controversial in Ireland. Almost 40,000 people signed a petition titled "Shamrock for Trump: Not in my name" demanding that Kenny cancel the trip.

During the U.S. presidential campaign, Kenny criticized Trump for his "racist and dangerous" language. Even so, the Irish leader followed through with the annual tradition on Thursday, prompting his staff and more than 20 Irish reporters to fly eight hours across the Atlantic to listen to the "Taoiseach deliver his well-polished son of the sainted shamrock routine along the east coast of America," as the Irish Times phrased it (Taoiseach, pronounced, TEE-shock or TEE-shuhck, is the Irish language title of the prime minister.)

And as the day went on, the awkward and at times embarrassing Irish cultural references from Washington politicians were nearly as bountiful as their green neckties.

At the luncheon, Trump shared what he claimed was an "Irish proverb."

"As we stand together with our Irish friends, I'm reminded of an Irish proverb - and this is a good one, this is one I like, I've heard it for many, many years and I love it," Trump said. "Always remember to forget the friends that proved untrue, but never forget to remember those that have stuck by you."

Irish tweeters immediately displayed skepticism:

A White House spokeswoman told the Hill the proverb was originally supplied in an email on March 8 by the State Department via the National Security Council "as building blocks in advance of this event."

She said the "building blocks" were provided in the context of the shamrock ceremony and were ultimately used in the prepared remarks at the luncheon. While a number of websites, Pinterest boards and books do indeed refer to the quote as an "Irish blessing," its origin was unclear.

Across social media, many pointed out that a poem by Nigerian poet Albashir Adam Alhassan includes a similar stanza.

The irony of the mishaps was that Trump has surrounded himself with Irish Americans, from presidential counselor Kellyanne Conway to press secretary Sean Spicer. Two of the leading Republicans involved in Thursday's cultural snafus — Pence and House Speaker Paul Ryan, — identify as Irish American.

Ryan introduced both Trump and Kenny at the luncheon, praising the United States' relationship with Ireland and lauding the nation for "all she has given us."

One of his statements caused a fair bit of head-scratching: "Americans, especially American Irish, are always try to endear ourselves to the Irish. Think about it. We went from a president who plays a lot of golf to a president who owns a lot of golf courses," Ryan said. "That is about the closest thing you can get to royalty in Ireland."

Trump, indeed, owns a golf course in Ireland, and has golfed in various courses at least nine times since taking office. And he recently played 18 holes with pro golfer Rory McIlroy, who is from Northern Ireland. But aside from that connection, some Irish people questioned the reference to royalty and golf, a sport that originated in Scotland.

But perhaps the most "appalling" moment of the day for some came as Ryan offered a toast, in honor of Ireland's visit.

While addressing the luncheon, Ryan suddenly pulled out a pre-poured pint of Guinness beer from under the podium.

"To what our forefathers have started and our children will continue, may the light always shine upon them. Sláinte."

The speaker may have used the correct word for the toast, but all Irish Guinness enthusiasts could focus on was that "despicable pint." Anyone who has lived in or traveled to Ireland knows the law of the land: a dark, Irish beer should always be topped with a creamy, white, thick foam.

One person tweeted she would be "ashamed" to be seen holding that pint. It looked like a pint "you find in the smoking area at the end of the night, its owner stumbled home long ago," said another.

The Journal, an Irish news website, summed it up this way: "Some questionable Guinness pouring going on in Washington by the looks of Paul D. Ryan's pint."