The Real Madrid footballer, 25, was in a playful mood as he tickled the Russian model, 24, as they relaxed by the rooftop pool of their New York city hotel.
Their loving display came after Shayk revealed she had been left 'deeply upset' over rumours surrounding her reaction to him becoming a father to a baby boy by surrogate.
Poolside: Cristiano Ronaldo relaxes in the sun outside his New York hotel as his girlfriend Irina Shayk issued a statement denying she was devastated by the news he had paid a surrogate to have his child
Shayk has been at the centre of reports that she knew nothing about the birth of the baby boy and a Facebook page in her name suggested she had been left in tears by her boyfriend's announcement.
The 24-year-old model, furiously denied the rumours in a statement issued by her spokesman, and said anything that was allegedly said in previous reports by her was fake.
It said: 'There have been rumors that have recently been publicised surrounding our client Irina Shayk's personal life and the birth of Cristiano Ronaldo's son.
'Any such statements allegedly made by Ms. Shayk are false. Furthermore, any statements allegedly made by Ms. Shayk regarding marriage at this time or wanting to have children at this time are also false, as recently printed by European tabloids.
Stunning: The 24-year-old Russian model showed off her incredible bikini body
Affectionate: The couple share a playful moment amidst the dramatic week
'It is unfortunate that individuals take it upon themselves to create fake fan pages and release false statements for any reason. For the time being, Ms Shayk has suspended her Twitter account in the wake of such rumors.'
The part talking to reports about the couple in European tabloids last week referred to suggestions that Ronaldo had proposed to Irina and they were planning to have a baby together.
In light of the news about the surrogate mother, postings on her Facebook fan page, claimed that she was 'devastated' about the surrogate son.
Fun in the sun: Ronaldo dives into the pool
'She is a private person and feels she is under siege. She just wants to carry on with her relationship with Ronaldo.'
Although becoming a father three weeks ago, Ronaldo appears to have spent little time with his son, having spent the past week shopping, partying and relaxing by the pool in New York with his girlfriend.
Meanwhile, back in the footballer's native Portugal, his mother and sister celebrated the new arrival to the family.
Mum Maria Dolores dos Santos Aveiro, and his sister Katia Aveiro, were snapped out in the port of Vilamoura, drinking pink champagne to wet the new baby's head.
Enjoying fatherhood then? Despite becoming a dad three weeks ago, Ronaldo has spent the past week shopping, sunbathing and partying
Toned: Ronaldo tickles his girlfriend's flat stomach
'Yes, Cristiano chose the name but we like it. We don't know the mother, we've never met her.'
Irina has stuck by her boyfriend since he made the announcement that he had become a father to a baby boy by a surrogate mother.
She met up with the Real Madrid star for lunch in Manhattan on Monday but took a friend along with her for moral support.
And later that night, she met up with Ronaldo for dinner at Chinese restaurant Mr Chow, but again, took a friend along with her on the night out.
She stuck close to model Jessica White, 26, and barely managed to raise a smile all night, looking deep in thought as she was snapped by waiting cameras.
Wetting the baby's head: Ronaldo's sister Katia (L) and mother Dolores went out in Portugal last night to celebrate the family's new arrival
The party then made their way to SoHo House for an after dinner party at the member's club.
The £180,000-a-week footballer broke the news about his baby son in the early hours of Sunday morning.
On his Facebook page, he wrote: 'It is with great joy and emotion that I inform I have recently become a father to a baby boy.
'As agreed with the baby's mother, who prefers to have her identity kept confidential, my son will be under my exclusive guardianship.'
The footballer's sister Katia Aveiro, speaking at her home in Vilamoura on the Algarve in Portugal, said the baby - born weighing 9lb 8oz on June 17 - had made her brother 'very happy'.
All the gang: Ronaldo, with his back to the camera, looks at Irina who avoids his gaze and flashes a dirty look to the cameras as they and their friends have a cigarette outside Mr Chow in New York earlier this week
The child is now said to be in the care of other members of Ronaldo's family in Vilamoura, including his mother Dolores.
Portuguese newspaper Diario de Noticias claimed the baby was conceived with a surrogate mother at the end of last summer in San Diego, where the Real Madrid star was on holiday.
A spokesman for Ronaldo's management company Gestifute confirmed he had become a father but refused to comment on the surrogacy claims.
He was said to have flown home to Portugal to see the baby as soon as the national team was knocked out of the World Cup.
A spokesman for Ronaldo's management company Gestifute confirmed he had become a father but refused to comment on the surrogacy claims.
He was said to have flown home to Portugal to see the baby as soon as the national team was knocked out of the World Cup.