Senedd member Sarah Cooper-Lesadd quits Reform to join Plaid Cymru
Getty ImagesA member of the Senedd has quit Reform and joined Plaid Cymru, saying Reform has "no interest in Wales".
Sarah Cooper-Lesadd's defection was approved by Plaid's Senedd group and national executive on Tuesday.
It means Plaid, which won May's Senedd election, now has 44 members , leaving Reform - the largest opposition party - with 33 seats.
Cooper-Lesadd, a former Conservative, was elected for the Pen-y-bont Bro Morgannwg constituency.
A Reform Wales spokesperson said the party had "planned to expel" her for supporting Welsh independence.
Cooper-Lesadd grew up in the care system and in a statement said she wanted to be a voice for care-experienced people "who are still badly under-represented in our politics".
"Reform has no interest in the work I came here to do," she said.
"They are far more interested in division, opposition and headlines than in finding solutions."
She added: "The party centrally has no interest in Wales.
"Their Senedd group is a staging post in the effort to get Nigel Farage into Downing Street, and that was glaringly obvious at its conference this week."
Her defection comes on the day Reform's leader in the Senedd, Dan Thomas, quit.

Plaid MS Marc Jones, chair of the party's Senedd group, said a decision to allow defections "is not taken lightly and "follows a period of reflection, discussion and a proper internal process".
He added: "It has been clear for some time to many of us that Sarah is sincerely motivated by a desire to make a positive difference, particularly for some of the most vulnerable people in our society.
"She has been honest about her political journey and has acknowledged that she was wrong to believe Reform was the right political home for her."
A Reform Wales spokesperson: "As soon as we discovered Sarah Cooper-Lesadd is in favour of Welsh independence and the break-up of the United Kingdom, we planned to expel her from Reform UK.
"Her separatist sympathies are not welcome in our party. Our policy on maintaining the Union is clear. Plaid are welcome to her, she is now in her third party in two years."
Additional reporting by Gareth Lewis
