"I am concerned that you appear to be unfocused on those critical services yourself," he said.
He said Mrs Joblin had not discussed these matters with the board nor had any direction from the board to write to him and, until she had that mandate, "I have no obligation or indeed interest in responding further to you".
He also targeted chief executive Julie Patterson, who he claimed "is totally unsuitable to remain in her role". He said findings from an Official Information Act request he made as well as media statements from the board "have and do substantiate that view".
Mr Solomon said the other matters raised by Mrs Joblin related to his rights as a New Zealand citizen "over which the board has no jurisdiction".
He claimed that this was not the first time she had "abused" her position as chairperson.
"I am vehemently opposed to the actions that the management arm of this DHB has taken with regards to provision of maternity services. I am delighted that my actions and those of others (mayor, council, midwives, the community and media) have forcibly brought about securing those services - at least in the short term.
THE CORRESPONDENCE
February 16: Email from Clive Solomon circulated to all staff at Wanganui Hospital prompts a complaint to the chief executive from one staff member as well as comment from others who Kate Joblin said were offended by some of the content.
February 17: Mr Solomon left the board meeting about two hours before it finished yet Mrs Joblin said she understood that at 5.25pm he was speaking on radio about the regional health plan. She said leaving the meeting to speak to media required an explanation.
February 21: Mr Solomon sent an email to board members, Wanganui district councillors and the media about proposing a motion of no confidence in the chief executive and board chair. She said he had been given a number of warnings in recent years about making statements regarding the performance of WDHB staff and again asked him to explain his actions.
March 1: Another email was sent by Mr Solomon to Councillor Rob Vinsen (and board members) referring to a clinician at the hospital in terms Mrs Joblin said were "disrespectful and critical".
March 30: He makes a press release about the investigation into a security guard closing doors on people marching to the hospital in protest at the regional women's health plan, asserting the instruction "most likely" came from the chief executive. He also questioned the integrity and honesty of a staff member investigating the incident.
"It is regrettable that the disgraceful actions of senior clinicians and very senior management had brought this hospital and our city to the brink of crisis and collapse," he said.
Mr Solomon said he would never compromise his "duty" in providing and ensuring safe, efficient and cost-effective healthcare for Wanganui.
The next round of board committee meetings are scheduled for tomorrow with the full board meeting on May 25.