Queen Elizabeth II on Wednesday thanked well-wishers for their messages of support after the death of her husband, Prince Philip, as she turned 95 and spent her first birthday without him in more than seven decades.

"My family and I would like to thank you all for the support and kindness shown to us in recent days," she said in her first public comments since his death on April 9 aged 99.

Queen Elizabeth II cut a solitary figure at her husband's funeral on Saturday
Queen Elizabeth II cut a solitary figure at her husband's funeral on Saturday POOL / LEON NEAL

"We have been deeply touched, and continue to be reminded that Philip had such an extraordinary impact on countless people throughout his life."

The Queen -- Britain's longest-reigning monarch -- said the messages from Britain, the Commonwealth and around the world had been a "comfort" during a "period of great sadness".

Her birthday falls during a two-week period of royal mourning for Philip, who was interred Saturday in the Royal Vault at St George's Chapel in Windsor Castle.

Queen Elizabeth II and Prince Philip, during a visit to Sierra Leone in 1961
Queen Elizabeth II and Prince Philip, during a visit to Sierra Leone in 1961 AFP / -

The Queen, seen at the funeral for the first time since his death, cut a solitary figure due to coronavirus restrictions, sitting alone in mourning black, with a white-trimmed, black face mask.

Close family, also masked, were forced to sit socially distanced in the historic 15th-century Gothic chapel during the 50-minute service attended by just 30 guests.

With the ongoing restrictions curtailing socialising, her birthday -- typically marked with a traditional gun salute and the release of a new portrait -- will be subdued this year.

Profile of British Queen Elizabeth II who turns 95 on Wednesday, April 21.
Profile of British Queen Elizabeth II who turns 95 on Wednesday, April 21. AFP / STF

Although the grieving monarch returned to public duties a few days after Philip's passing, there are no plans to mark her birthday publicly.

In the Buckingham Palace statement, however, she said: "I have, on the occasion of my 95th birthday today, received many messages of good wishes, which I very much appreciate."

Although the grieving monarch returned to public duties a few days after Philip's passing, there are no plans to mark her birthday publicly
Although the grieving monarch returned to public duties a few days after Philip's passing, there are no plans to mark her birthday publicly POOL / Kirsty Wigglesworth

She is expected to be at Windsor Castle, west of London, where she and the late duke had spent much of the past year shielding due to the pandemic.

"This is going to be a private day for her and that's how it should be," said Joe Little, managing editor of Majesty Magazine.

"I think she will be personally devastated by this, but I don't think the death of the Duke of Edinburgh, her husband of 73 years, is going to impact on her working role.

Queen Elizabeth II is marking her 95th birthday during the two-week period of royal mourning following the April 9 death of the 99-year-old Duke of Edinburgh
Queen Elizabeth II is marking her 95th birthday during the two-week period of royal mourning following the April 9 death of the 99-year-old Duke of Edinburgh POOL / Jonathan Brady

"There's the public queen and there's the private queen, and she's great at being able to compartmentalise."

Prime Minister Boris Johnson tweeted "warm wishes" to the monarch.

"I have always had the highest admiration for Her Majesty and her service to this country.

"I am proud to serve as her Prime Minister," he wrote.

The Queen, now in the twilight of her reign, married Philip in November 1947, nearly five years before she succeeded her father, king George VI.

She has previously described him as her "strength and stay" during seven decades of almost constant presence at her side.

Senior royals have conceded his death has left a "huge void" in the Queen's life, and have reportedly been sharing responsibility to comfort her at Windsor.

The Queen and Philip's grandson Prince Harry, 36, flew back from the United States for the funeral, but returned home again to be with his pregnant wife Meghan before his grandmother's birthday, according to The Sun.

Saturday was Harry's first public meeting with the family since a reported falling out over his shock move to California, and his stinging criticism of royal life, including accusations of racism in the institution.

He reportedly spent several hours with his father and heir to the throne Prince Charles, and elder brother Prince William following the ceremony, prompting speculation that any enduring rift is being healed.

Although the Queen's birthday is on April 21, her official birthday is normally celebrated on the second Saturday in June, in a tradition dating back to 1748.

It is marked with an annual military parade, known as "Trooping the Colour", but has been cancelled for a second consecutive year due to the pandemic.