Instructions: In this task, you are given an article. Your task is to summarize the article in a sentence.
Input: Joe Smyth, who achieved UKIP's highest vote share in Wales in 2015, said Mr Gill showed "no leadership" during its turmoil over assembly poll selections.
Another three general election candidates, two standing in May's poll, have also called for Mr Gill to go.
A UKIP Wales spokesman said Mr Gill had "stood up constantly" for "proper representation" for the Welsh members.
On Tuesday, Mr Gill announced local members would now decide the rankings for UKIP's regional list candidates, seen as the party's best hopes for winning seats.
Mr Smyth, re-selected for Islwyn at May's assembly election, said Mr Gill should have insisted the Welsh party ran whole the selection process.
There were complaints within the party about the original plan for its National Executive Committee (NEC) to have the final say.
Mr Gill has described the move to give local branches a vote over the final rankings as a "great victory" over the NEC.
But some remain unhappy that former Conservative MPs Neil Hamilton and Mark Reckless are still in the running for selection.
At the general election, Mr Smyth won 19.8% of the vote in Islwyn.
Despite being re-selected for the constituency for the assembly poll, he pulled out of the regional list selection in protest at the way it was being organised.
Mr Smyth told BBC Wales both Mr Gill and the NEC had treated members, activists and candidates with "contempt".
"He's trying to make out now that he's saved the selection process by allowing the Welsh members to vote on the candidates, it's a fallacy," he said.
"Nathan was responsible and agreed to how the selection process was going to be run at the very beginning.
"It's completely and utterly farcical."
Accusing Mr Gill of "weak leadership", Mr Smyth called for him to "resign straight away".
The criticisms were endorsed by Blair Smillie, UKIP's candidate for Alyn and Deeside at the general election.
"Nathan Gill has been terrible, he has to go," he said.
"There is no leadership in Wales, the organisation in north Wales is in disarray."
Nigel Williams, standing in the Delyn constituency in May after running for UKIP in 2015, said he had been "concerned for some time we lack leadership across Wales".
"We've let the general election momentum slip, we need better leadership," he said.
Ken Beswick, UKIP's Torfaen general election candidate added: "Nathan Gill is not suitable as a leader - he has no backbone.
"He's very close to Nigel Farage and won't stand up to him."
Responding to the criticism, a UKIP spokesman said: "Far from being weak he's actually been very determined in his commitment to ensuring the process is not controlled by party elites.
"The selection process has been deeply complex to ensure the best outcome; there will always be people dissatisfied.
"We think putting the decision in the hands of the membership is the most democratic option.
"All candidates that will be submitted to the membership have been rigorously vetted to ensure the highest calibre candidates are put forward to represent UKIP Wales."
Output:
Four former UKIP general election candidates have called for the party's Welsh leader Nathan Gill to resign.