Plaid Cymru’s leader Adam Price has confirmed it is in talks with other pro-EU parties over the Brecon and Radnorshire by-election.
The party is considering whether it should stand a candidate or agree to a pact with another party.
The vote has been triggered after 10,005 people signed a petition to remove the Tory MP Chris Davies.
Labour, the Lib Dems, and the Brexit Party are expected to run candidates against the reselected Mr Davies.
The recall petition was set in motion after Mr Davies pleaded guilty to a false expenses claim.
Mr Price told BBC Radio Cymru’s Post Cyntaf that Plaid is “in discussions with other pro-Remain parties – parties that want to stay within the European Union – at the moment and, of course, with our members locally”.
“In light of those discussions, we will make a decision before long.”
It is understood the Lib Dems, Change UK and the Greens have been approached.
Plaid would want something out of the arrangement if it did agree not to field a candidate, and such a decision would have to be part of a pact, BBC Wales was told.
Plaid polled 1,299 votes at the 2017 general election.
“Change UK is happy to confirm that we are in talks about a joint independent Remain candidate in the Brecon and Radnorshire by-election,” a spokesman for the party said.
On Sunday night local Conservative party members confirmed Mr Davies would be the candidate for the upcoming by-election.
“The members took the view that we want somebody local, that knows the area, knows the patch, knows the issues, goes to every agricultural show, goes to every church service and other events in Brecon and Radnorshire,” Brecon and Radnorshire Conservative chairman Peter Weavers said.
“He’s well liked, he’s well respected and well known in the area. And that’s what people want, they don’t want people dropped in from London, absolutely no knowledge of the constituency.”
Mr Weavers said Mr Davies would fight the by-election “on his track record, which is superb. We’ve heard Brecon and Radnorshire mentioned in Westminster more times in the past four years than in the previous 20.”
He said most of the constituency did not sign the petition.
“43,000 people didn’t sign the petition to remove Chris Davies. At the last general election over 20,000 people voted against the Conservative party in this constituency,” he said.
Mr Davies polled 20,081 votes in 2017, versus the Lib Dems’ 12,043. Labour chalked up 7,335, while UKIP was given 576 votes.
A date has not been set for the by-election. Jane Dodds, Welsh Liberal Democrat leader, is planning to stand for her party.
Tom Davies, a town councillor in Brecon, has been selected for Labour. The Brexit Party is yet to announce its candidate, while it is understood UKIP may be taking part.
A Welsh Liberal Democrat spokesman said: “By adopting Chris Davies again the Conservatives have demonstrated they can offer nothing more than an MP embroiled in controversy.”