The 27-year-old defender will officially link up with manager Emma Hayes’s side on New Year’s Day.

Centre-back Fahey has more than 50 international caps to her name and was a key member of the Arsenal Ladies side that won the FA Women’s Cup last term. She also won the treble with the club in 2008.

‘I’m very excited to be joining Chelsea Ladies and am looking forward to working with a great squad of players and management team,’ said Fahey.

‘The structure and future plans of Chelsea matched my ambitions and I'm really looking forward to getting started in January.

‘The opportunity to play Champions League football was also a big factor and testing yourself against the top European teams is something every player wants.

‘This is a new challenge, where I can add strength to the existing qualities I have and hopefully help Chelsea Ladies to be successful in the future.’

Fahey has been named FAI Women's Senior International Player of the Year on three separate occasions and in her time with Arsenal she won five league titles, five FA Women’s Cups and the FA Women’s Premier League Cup.

Chelsea Ladies manager Hayes is delighted to have added the defender to her ranks ahead of a season which includes our first tilt at the UEFA Women’s Champions League.

‘Niamh is one of the most underrated players in this league,’ said Hayes. ‘Her character, winning mentality and experience sets her apart.

‘She is a fantastic one v one defender and has quality in both feet to help play the Chelsea way. She will take our game to another level and is a player I have admired for a long time.’

Fahey is Chelsea Ladies’ third signing this winter following the arrivals of winger Gemma Davison and midfielder Millie Bright.