Plaid Cymru in Brecon and Radnorshire by-election pact talks
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 vote has been triggered after 10,005 people signed a petition to remove Tory MP Chris Davies, who was reselected on Sunday night.
Labour, the Lib Dems and the Brexit Party are expected to run candidates against Mr Davies.
Plaid is considering whether it should agree to a pact and not take part.
The recall petition was set in motion after Mr Davies pleaded guilty to a false expenses claim.
The Speaker of the House of Commons, John Bercow, confirmed on Monday that Mr Davies had ceased being an MP following the petition.
Conservative chief whip Julian Smith said his party will move the writ for Brecon and Radnorshire on Tuesday - the process that will kick-start the by-election process.
Once agreed by the Commons the by-election is likely to take place on 25 July or 1 August.
Mr Price told BBC Radio Cymru's Post Cyntaf that Plaid is in discussions with "parties that want to stay within the European Union" and with local members.
"We will make a decision before long," he added.
It is understood the Lib Dems, Change UK and the Greens have been approached. Plaid would want something out of the arrangement if it agreed not to field a candidate, BBC Wales was told.
The party polled 1,299 votes at the 2017 general election.
Jane Dodds, the Liberal Democrat candidate and Welsh Liberal Democrat leader, said her party does not talk about arrangements with other parties in public.
"They are for discussions that are not in the media," she said, adding she would be standing on the ballot paper as a Welsh Lib Dem.
"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.
The Wales Green Party claimed there had been "no direct contact" with Plaid on the subject of the by-election, although a Plaid source said this was incorrect. A spokeswoman for the Greens said: "The decision to stand a candidate, or not, is one for the local party to make and is something they will be currently considering."
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," the local Conservative party chairman Peter Weavers told BBC Radio Wales' Breakfast programme.
Mr Weavers said Mr Davies would fight the by-election "on his track record, which is superb".
He said most of the constituency did not sign the petition.
"43,000 people didn't sign the petition to remove Chris Davies," Mr Weavers said.
Brexit Party leader Mark Reckless said: "Talk of a remain electoral pact in Brecon and Radnor shows that the only credible opposition party in Wales is the Brexit Party."
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.
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.