Liberal senator David Fawcett has apologised after making a “poor choice of words” in parliament that appeared to describe asylum seekers coming to Australia seeking protection as “fleas”.

Fawcett’s comments were made during a Senate estimates discussion on asylum seekers arriving by boat, saying the Labor party had “brought the fleas” and was now attempting to “nitpick” in parliament with questions over asylum policy cost blow-outs, wasteful and unauthorised spending.

“I just do question the ethics of nitpicking when your particular group perhaps brought the fleas in the first place,” he told the hearing at Parliament House, directing his comments at Labor members.

Unknown senators on the committee said “hear hear”, while Fawcett’s fellow Liberal and committee chair Ian McDonald was heard on the microphones to say “nicely put”.

Following the comments, Fawcett sought to clarify that he had intended to suggest that Labor had created the “irritation” of stress within the immigration department, not that he was characterising asylum seekers as fleas.

But he made a further late-night apology to the Senate.

“I have just been on the phone to Mr Phil Glendenning, the president of Refugee Council of Australia,” Fawcett said. “He has outlined how the words I spoke earlier today have been taken, and the deep hurt that this has caused across the network of communities that his council represents.”

“Whilst it was never my intention that my comments would refer to refugees in such a way, it’s clear that my poor choice of words has caused hurt to many people, and consequently I sincerely apologise.”