Activist Ethan Floyd will promote the Global Sumud Flotilla from Australia while fellow Novocastrians Zack Schofield and Cameron Tribe remain overseas.
Mr Floyd was greeted by his family and a group of supporters when he arrived in Sydney on Monday night, several days after being released from Israeli detention.
The Pro-Palestine activist was among 175 people who participated in the Global Sumud Flotilla of more than 100 boats that was intercepted in the Mediterranean Sea attempting to breach the Israeli naval blockade of Gaza.
After his boat was captured in international waters about 1400km from Gaza, Mr Floyd spent two days on an Israeli prison ship before he was allowed to return home from the Greek island of Crete.
While Mr Schofield, Mr Tribe and three other Australians have remained in Greece to work on further missions, Mr Floyd said he would promote their work from Australia.
"After we were released all of the Australians agreed that someone had to come back to Australia," he said.
"We've just gone through two days of inhumane treatment, and someone needs to be in Australia to tell that story.
"I can fulfil that role and make sure this isn't just something we're talking about after the fact, but something that we can keep people's attention on, that's an important role."
Despite last week's setback, Mr Floyd said he was confident the mission would achieve its goal of delivering aid to Gazans.
"As we speak, there are people back in Crete and in Italy and further along the Mediterranean who are considering how do we continue responsibly," he said.
"Even though we've just gone through two days of pretty intense and cruel treatment in jail, Israel didn't even manage to intercept half of our fleet. We only had 22 boats intercepted, and there's something like 40 that made it into Greek territorial waters.
"While they managed to give a few of us a really hard time, more than half of our fleet managed to evade interception, and they're getting ready to make the next leg of the journey."
Mr Floyd said there were similar motivations between involvement in climate activism in Newcastle and participating in the Gaza aid flotilla.
"I think there's something to be said about coming from the world's largest coal port and heading into what's been described as the world's largest open air concentration camp," he said.
"We've grown up in this place and we've seen how political power works. The same shitty things are happening all around the world and we are trying to do something about it."
Among those waiting for Mr Floyd's arrival were Greens politicians Mehreen Faruqi, Sue Higginson and Jenny Leong.
All spoke of their desire for further sanctioning of the Israeli government.
"We are so proud of Ethan and the others who have had the guts ... to step up where our government has miserably failed," Senator Faruqi said.
