It was announced in June that there would be three, 30-minute Christmas specials, following the immense success of the show.

Many fans commented on Ferretti’s post, saying they are “so excited” and “can’t wait to see Mr and Mrs Hayward on screen”.

Russell T. Davies, the Swansea-born writer behind shows including Doctor Who and Channel 4’s It’s a Sin, also said online that he “can’t wait”.

Another commented: “This is such a sweet series. It’s like a warm cosy blanket on a snowy winter day.”

The Christmas special has been produced by Cardiff-based Bad Wolf, and filming took place over summer, primarily in Wales.

Ruth Jones previously said the series was “one of the happiest jobs” she had ever done and “I love coming back to Wales”.

The first series was primarily filmed in south Wales, such as in Merthyr Mawr in Bridgend, the Gower peninsula, near Swansea and Brecon, in Powys, mid Wales.

The final episode of the first series saw Mary (Ella Bruccoleri) agreeing to wed Tom Hayward (Donal Finn).

The Christmas special is due to explore “what happens after the wedding bells fade and real life begins”, executive producer Jane Tranter said.

Tranter said the audience response to the series had “exceeded even our most optimistic expectations”.

“These Christmas specials give us the chance to spend a little more time with characters audiences have taken to their hearts,” she said.

As well as being hugely successful in the UK, the first series also attracted a wider audience via BritBox North America, and notched up 250 million media views across BBC accounts on TikTok, YouTube, Instagram, and Facebook.

The specials are expected to premiere during the festive period on BBC iPlayer and BBC One.

In the US and Canada, it will be available on BritBox.