Members of a far-right nationalist group converged on the ABC's Melbourne office on Saturday to protest against Islam and the national broadcaster's Q&A program.

Seven members of the United Patriots Front protested against Zaky Mallah's appearance on Q&A outside the Southbank building's front door.

The small group of demonstrators gathered about 2pm and spoke to reporters.

The anti-Islam group waved Australian flags and appeared to cook a pig on a spit.

ABC staff were told not to leave via the front door, ABC journalist Loretta Florance tweeted.

Staff at @abcnewsMelb being told not to leave via the front door as United Patriots Front protest outside. pic.twitter.com/7WWZUuj2Jz— Loretta Florance (@dhflorance) June 27, 2015

One protester told the media: "In here [the ABC] public opinion is shaped artificially. It's not democratic. It's not Australian".

The group left a short time after.

On their Facebook page, the United Patriots Front declare themselves as a movement "opposing the spread of Left Wing treason and spread of Islamism".

The ABC has been heavily criticised this week for allowing Zaky Mallah, a terror suspect who admitted to threatening to kill Australian security officials but was acquitted of the charges, to appear on Q&A.

The United Patriots Front protesting outside @abcnewsMelb over Zaky Mallah on @QandA. #7NewsMelb pic.twitter.com/EReaHR9JB6— Paul Dowsley (@pauldowsley7) June 27, 2015

The ABC confirmed it had received a number of threatening phone calls since Monday's episode of Q&A and had stepped up security at major ABC offices across Australia.

An ABC spokesman would not comment on Saturday's protest.

He would also not say how many threatening phone calls the ABC had received or if any had been referred to police.