Simon Cowell offered to send a plane for Carlos Marin to fly him to Spain for treatment before his passing.
The 53-year-old Il Divo singer died on December 19, days after being hospitalised with COVID-19.
Carlos was placed in a coma by doctors at Manchester Royal Hospital in England, before losing his battle with the virus.
And the late star's ex-wife, Geraldine Larrosa, has revealed the 'X Factor' boss - who put together the classical crossover group for his Syco label in 2003 - was a huge support in the days leading to her husband's death.
Speaking to Spanish publication Hola!, Geraldine said: “Simon Cowell personally phoned the hospital and offered to help with anything.
"To help him, send him a plane in case they could fly [to Spain] sooner.
“But it was impossible.
“He was very sick and he would not have survived the pressure of the plane."
Simon has been left "devastated" by his friend's passing.
The 62-year-old television personality said in a touching tribute to the star: "I am finding this so difficult to put into words how I feel right now.
"I am devastated Carlos Marin has passed away. He loved life. He loved performing and always had so much appreciation towards the fans who supported the group from day 1. Rest in peace Carlos. I will miss you."
Il Divo - which also features Urs Buhler, David Miller, and Sebastien Izambard - had shared the news of Carlos' passing on their social media accounts.
They wrote: "It is with heavy hearts that we are letting you know that our friend and partner, Carlos Marin, has passed away. He will be missed by his friends, family and fans. There will never be another voice or spirit like Carlos.
"For 17 years the four of us have been on this incredible journey of Il Divo together, and we will miss our dear friend. We hope and pray that his beautiful soul will rest in peace. With Love -- David, Sebastien and Urs (sic)"