Plaid Cymru conference: Wales 'let down by Labour'
Labour has "let Wales down", Plaid Cymru's deputy leader said on Saturday.
Helen Mary Jones told her party's spring conference that Labour wants to only "cover their own backs" instead of standing up for Wales.
Labour MP Nia Griffith responded, saying "only one party in Wales has ruled out any deal with the Tories" in the assembly election.
Ms Jones also outlined Plaid's plans for the NHS.
The party has said it will renegotiate contracts for doctors and dentists as part of an attempt to give patients more choice about accessing healthcare.
She will tell the party faithful in Cardiff that Plaid will offer voters a "clear alternative" at May's assembly election.
Plaid has been in a coalition government in the assembly with Labour since the last elections in 2007.
After a four-year truce, Plaid has used the conference in Cardiff to ratchet up its attacks against its coalition partners.
In his conference speech on Friday, Plaid leader and Deputy First Minister Ieuan Wyn Jones joked that the two parties had "started divorce proceedings".
He attacked "a culture of excuses which has been fostered and bred by the Labour Party for most of the last 12 years".
Later Ms Jones will say: "People in Wales have been let down by Labour.
"Their claims to 'stand up for Wales' would be a joke if they were not so insulting.
"This is the party that came to power in 1997 and were relaxed about the fact that under their watch the gap between the rich and poor was wider than ever."
She will say Labour led the country into two "unjust and illegal wars".
"Fortunately people in Wales have a clear alternative to the Westminster parties," she will say.
In his speech, Heritage Minister Alun Ffred Jones will say Plaid can point to achievements during its time in office, including legislation from his department to bolster the status of the Welsh language.
He will say: "Without a Plaid Cymru presence in government the steps forward we have taken and will count for nothing.
"Without Plaid Cymru in government the distinctive Welsh approach will be lost."
Party leader Mr Jones has stopped short of explicitly ruling out talks with the Conservatives and Liberal Democrats if May's election is inconclusive, although he says it would be "difficult" to form a coalition with them in the assembly because of the actions of the two parties' UK government in Westminster.
Labour MP Nia Griffith said: "Only one party in Wales has ruled out any deal with the Tories and that is Welsh Labour - the true party of Wales."