Alberta Finance Minister Doug Horner is trying to convince members of the Progressive Conservative caucus that calls for his resignation are unjustified.

An email Horner sent his colleagues over the weekend was widely leaked and posted online.

Horner admits in the letter that some Tory MLAs want him to step down over allegations that his department — which oversees the use of government aircraft — failed to prevent the misuse of the fleet by former premier Alison Redford, as outlined by the auditor general last week.

Last week the Wildrose Party issued a list of five reasons Horner should step down. Horner rebuts those points in his letter to the caucus.

“I will not let the fear of the opposition or media bully me into someone thinking that my reputation and contribution is tarnished by the actions of a few outside of my control,” he wrote.

Horner said while he is in charge of the planes, whoever books the aircraft is responsible for following the rules.

“My office role is to request that they follow the policy as outlined and that it is for government business and any "invited guests" are approved by the requesting officer,” he wrote.

“You will know that anyone wishing to join a flight does not get "approval" from my office but from the Ministry requesting the flight.”

Horner also vows in the email to fully implement the recommendations made by Auditor General Merwan Saher regarding the use of the government aircraft.

PC leadership candidate Thomas Lukaszuk said he doesn’t care if Horner stays or leaves as finance minister.

Lukaszuk said if he is elected leader, he would get rid of most cabinet ministers anyway.

"If I am so lucky as to be the premier you are going to see a major house cleaning at the top without a doubt and the cabinet will look significantly different,” he said.

So resigning at this point or not resigning is frankly quite irrelevant because you will see a much different structure in place, a very different cabinet."