A leaked text conversation between Spain’s Queen Letizia and a businessman embroiled in a banking scandal has caused a furore, as King Felipe VI attempts to revive the scandal-hit monarchy.

In the text conversation, the queen pledges her support for Javier López Madrid – a close friend of the king – and calls him her “yoga mate”.

The iMessage conversation, revealed by the online daily eldiario.es, dates back to October 2014. The businessman is among dozens accused of personally misusing bank funds.

The scandal allegedly involved executives and board members at Caja Madrid and Bankia – the group whose near-collapse provoked an EU bailout of Spain’s financial sector – use credit cards given out by their employer to spend about €12m (£9.3m) on themselves.

“I wrote to you when the story on the credit cards came out,” Letizia wrote, according to El Diario. “We know who you are and you know who we are. We know each other, like each other, respect each other. To hell with the rest. Kisses yoga mate (miss you!!!)”

López then thanked her. “In future I will take extra precautions, we live in a very difficult country and I will be even more aware of my conduct.” The king himself then joined the conversation, saying: “We do indeed!”

The king has tried hard to clean up the royal family’s image after a corruption scandal involving his sister that precipitated his father Juan Carlos’s abdication in June 2014.

Last week Princess Cristina gave evidence in a corruption case centred on her husband’s business dealings – the country’s first member of the royal family to face criminal charges since the monarchy’s 1975 restoration.

The case has sullied the reputation of the monarchy and become a symbol of perceived corruption and greed among Spain’s elites. Spanish social media users have revelled in the royals’ embarrassment about the leaked conversation.

“Spain is a very difficult country,” @ElPerricano tweeted above a photo of an old lady rummaging through rubbish juxtaposed to a shot of the royal family on a yacht.

The hashtag CompiYogui – the Spanish term used by Queen Letizia loosely translated as “yoga mate” – was the biggest trending topic on Twitter in Spain.

Many jokingly used bears to illustrate their tweets in reference to the cartoon character Yogi Bear. “CompiYogui attacking public money,” @ulises_sevilla tweeted above a short segment of the scene of a bear attack in the Oscar-winning film The Revenant.

A spokesman for the palace, who refused to be named, told Agence France-Presse that the king and López were no longer friends due to the businessman’s judicial issues. “The king doesn’t directly explicitly support him [López],” he added when asked about the messages. “It’s different for the queen, who is clearer.”