Plaid Cymru MPs would vote in favour of a further referendum on the final Brexit deal, the party's leader has said.
Adam Price said he would campaign to keep the UK in the European Union.
He said such a vote should have an option to stop Brexit.
"The land of milk and honey promised by the Brexiteers now looks more like it will be sustained by Spam and potato peel pie," he told the SNP's autumn conference in Glasgow.
On Sunday Nicola Sturgeon said her MPs would support a new referendum if it were put to them.
Delivering the fraternal address at the SNP gathering, Mr Price confirmed Plaid's four MPs would join the SNP in voting for a new poll "which will include remaining within the European Union as one of its options - for which we will campaign as clearly the best outcome for our respective nations".
There are currently no plans to put any such proposal in front of MPs, and the Prime Minister Theresa May has vowed not to "give in" for calls for a fresh poll - known by supporters as a "People's Vote".
Labour activists have backed keeping all options open - including a new referendum - if MPs are deadlocked over Brexit.
Mr Price told SNP delegates: "We have to be honest too about the destructive potential of a bitter, brittle Brexit.
"The British political establishment have proven themselves singularly unable to deliver anything for our nations - and Brexit is no exception."
Mr Price, who has made Welsh independence a central part of Plaid's message, said: "Brexit has laid bare in excruciating detail that Britain's already broken; its democracy dysfunctional, its economy unbalanced, its society unequal.
"The old Britain is dying. Let it die."