Calls for an investigation into a £200,000 donation to Welsh First Minister Vaughan Gething have intensified in recent weeks.
A motion calling for an independent probe into the money was debated in the Senedd on Wednesday and defeated by 27 votes to 25.
But former deputy climate change minister Lee Waters said Mr Gething should do “the right thing” and return the donation.
Mr Gething was elected leader of Welsh Labour in March and succeeded Mark Drakeford as Wales‘s first minister.
Opposition parties launched a bid to appoint an independent advisor to check whether there was any conflict of interest over the donation during the leadership campaign.
Mr Gething says it was within the rules and declared in line with party protocols.
A separate debate took place on whether to introduce a cap on political donations. That motion was also defeated.
When asked about the issue at PMQs, Rishi Sunak said “answers” were needed and that the matter was “not at all transparent”.
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Why are there calls for an investigation?
During the Labour leadership campaign, the Gething camp received a £200,000 donation in two separate transactions from a company called Dauson Environmental Group.
It emerged the company had also submitted a planning application for a solar farm.
Due to the size of the application, it will require Welsh government approval.
Mr Gething would not be able to make decisions in relation to the application in accordance with the ministerial code, as Dauson is a business within his Cardiff South and Penarth constituency.
Less than a year before the donation was made, a subsidiary company received a £400,000 loan from the Development Bank of Wales, which is owned by the Welsh government.
What are opposition parties saying?
Andrew RT Davies, leader of the Welsh Conservatives, said the Gething government had “stalled before it could get going”.
“We need to see a full, independent investigation into Gething’s campaign finances,” he added.
Plaid Cymru leader Rhun ap Iorwerth said “sleaze… threatens to rear its head in Welsh politics”.
“The first minister either knew of the donor’s convictions and thought nothing of it or failed to undertake due diligence,” he said.
What do Mr Gething’s Labour colleagues say?
Several members of the Senedd have expressed their support for Mr Gething, but Lee Waters told the chamber on Wednesday that he felt “uncomfortable” with the donation and called for it to be returned.
“Sometimes doing the right thing is the hardest thing, but you rarely regret it in the end,” he said.
Mr Gething’s leadership rival Jeremy Miles previously told the BBC that he would not have accepted the donation.
Ken Skates, transport secretary and prominent Gething backer, has also distanced himself from the donation.
He told the BBC he “didn’t have anything to do with the donation” and the campaign team had been “assured” it would not affect future decisions made by Mr Gething.
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What has Mr Gething said?
Mr Gething has so far refused calls for an independent inquiry and has said he will not return the money.
He said the donation was within the rules and that it had been declared in line with party protocols.
Mr Gething has, however, appointed former first minister Carwyn Jones to lead a review into political donations.
But opposition parties have accused Welsh Labour of “marking their own homework”.
What does Dauson Environmental Group say?
The company’s director David Neal said that no part of the loan it received from the government-owned Development Bank of Wales contributed to the donations to Mr Gething’s campaign.
Mr Neal said the business made the donation to Mr Gething because it felt that he was “the best person for the job”.
“Dauson Environmental Group has not engaged with Vaughan Gething or his ministerial department regarding any planning applications and we would not expect him to have any involvement in these decisions,” he added.
Mr Neal also told Sky News that he would be “happy to cooperate” with an investigation if one were instigated.