The 90-year-old monarch has been battling a "heavy cold" since before Christmas
Queen Elizabeth
Credit: Kirsty Wigglesworth/AP

Queen Elizabeth II missed church on New Year’s Day – a week after canceling her annual trip to Christmas mass for the first time in decades as she battles a heavy cold.

“Her Majesty The Queen will not attend Sunday worship at Sandringham today,” Buckingham Palace said in a statement released early Sunday.

“The Queen does not yet feel ready to attend church as she is still recuperating from a heavy cold.”

Still, a palace spokesperson tells PEOPLE that she is “up and about in Sandringham House. She is working, taking papers as normal. She is working as normal but she’s decided not to go out to church.”

Her absence from two consecutive high-profile appearances underscores how seriously doctors are taking the 90-year-old sovereign’s illness.

Credit: Andrew Parsons/i-Images/ZUMA Wire

After canceling their annual train trip to Sandringham Estate for Christmas due to “heavy colds,” the monarch and Prince Philip, 95, were well enough to travel the following day by helicopter. However, the Queen was forced to drop out of the royal family’s annual walk to church on Christmas morning as she continued to recover.

“Her Majesty The Queen will not attend Church at Sandringham this morning,” a Palace spokesperson said in a statement obtained by PEOPLE. “The Queen continues to recover from a heavy cold and will stay indoors to assist with her recovery. Her Majesty will participate in the Royal Family Christmas celebrations during the day.”

The Queen’s last public appearance was Dec. 9, when she hosted the ambassador of Liberia for a private audience at Buckingham Palace. She also made an appearance across the realm during her pre-recorded Christmas broadcast. It also marked her first outing since she was the victim of a Twitter death hoax last week.

Philip, who was also still under the weather; Prince Harry; Prince Charles; Camilla, Duchess of Cornwall; Sophie, Countess of Wessex; Prince Edward and Princess Eugenie attended a Christmas church service at St. Mary Magdalene church on the Queen’s Sandringham estate in Norfolk. Typically, the entire royal family walks together to a church service in the late morning but the royals chose to go to an earlier service on Sunday.

Credit: Andrew Parsons/i-Images/ZUMA Wire

Elizabeth wasn’t the only royal who missed out on the Sandringham Christmas walk — Prince William, Princess Kate and their two children Prince George and Princess Charlotte chose to spend their holidays with Kate’s parents. The Queen’s granddaughter Zara Tindall and her family also skipped out on the services after she revealed on Christmas Eve that she had suffered a miscarriage. Zara and her husband Mike Tindall were expecting their second child.

Philip, Princess Anne, and Prince Edward and their families were spotted at the New Year’s Day service on Sunday.

–with reporting by SIMON PERRY