Vermaelen is aware of growing supporter unrest as Arsenal's struggles continue.
"Sometimes, as a player, you are frustrated as well," he said.
"If you lose you get frustrated but it's not the right thing to act on, we have to stick together, work hard. We need each other.
"They [the fans] must not forget that we need them because they belong to the team and to the club.
"We must stand behind each other, that's the only thing we can do."