His comments follow from an error last week, in which Mr Key was forced to correct an answer he gave to Parliament that he had not been in touch with Slater recently.
He also told reporters he could not remember when he had last had a text message from the blogger, when it had been the night before.
That contact took place before the release of a report which detailed co-operation between Slater and Mr Key's staff to conduct a political smear against former Labour Leader Phil Goff using information supplied by the SIS.
Late on Wednesday night Mr Key released the transcript of a text exchange between himself and Slater which took place on Monday night, before the release of Inspector-General of Intelligence and Security Cheryl Gwyn's report.
Labour leader Andrew Little told Radio New Zealand more questions would be put to Mr Key in Parliament this week about his response to questions regarding Slater.
Mr Key told RNZ he did not want to be specific in answering reporters' questions that related to contact between him and Slater.
"Because an awful lot had happened around that time.
"I was rushing. I'm prepared to accept I should have actually phrased that in a better way, still without being specific."
In the past three months he had not "proactively" been in touch with Slater, but would sometimes reply to messages from him, Mr Key said.
Details of the contact between the pair came to light after a screen shot was made public of Slater discussing with another person that he had recently spoken with the prime minister.
Mr Key told RNZ if that had not been released, he would not have realised his mistake in Parliament.
He repeated his assertion that he did not hear the question in full in Parliament because of the noise at the time, which was why the mistake was made.
He would continue with his policy of not contacting Slater, he said.
"We still see him as a member of the media and there are people in the media who send me text messages that I respond to from time to time.
"But there won't be massive engagement."
