In a further development in the row, a Welsh Labour spokesman had this to say .
Hearing Leanne Wood and Plaid Cymru banging on about tribalism once again is as pathetic as it is predictable, coming as it does from a party whose guiding principle is the indisputably tribalist politics of separation.
Welsh Labour remains as proud as ever of its long and deep rooted bond with its affiliated Trade Unions and we were disgusted by Leanne Wood's inaccurate and vindictive attack on the good work that they do.
But people in Wales will see her claims for what they are-the grubby politics of a leader who has already lost her way and the support of much of her party.
The spokesperson went on to say
There are many reasons why Trade Unions remain deeply suspicious of Plaid Cymru.
Plaid's threat of separation, threat to the UK economy, threatening to tear up pay bargaining arrangements, telling lies about the Welsh Union Learning Fund and calling development grants for working people "bribery" are just some of them.
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