"The current chaotic performance of the EU and European governments should make us red in the face with shame," Fischer told this week's edition of newspaper Die Zeit.
Not known for pullling punches, he said there is a travelling "EU troika replete with foreign ministers, while the French president competes with the attempt. With this we make ourselves laughable as Europeans. It's a diplomatic flea circus."
Fischer, who served as foreign minister under former Chancellor Gerhard Schröder from 1998 to 2005, urged current Chancellor Angela Merkel to solidify a unified position on Middle East policy in the EU without using too much "German weight" to do so.
Solidarity with Israel is essential, he said. "There I have to come to the government's defence," Fischer told the paper. "We show solidarity with Israel across party lines, and that has been part of our reason of state since the country was founded."
Over the weekend Germany called for efforts towards a ceasefire in Gaza to intensify but said that any truce must ensure Israel's long-term security.
The comments came as Israeli soldiers and tanks pushed into Gaza, after a week of aerial bombardment in which hundreds of Palestinians have reportedly died. Rocket fire from Gaza over the same period has killed several Israelis.
The Israeli ground offensive in the Gaza has disturbed many in Germany and though Merkel has blamed militant Islamist group Hamas for provoking the Israeli military assault, she has also been widely criticised in some quarters for not pushing harder for a ceasefire.
Meanwhile, German Foreign Minister Frank-Walter Steinmeier said Wednesday afternoon that he supported a ceasefire plan suggested by Egyptian President Husni Mubarak.
"With this as a foundation, we have to find the quickest way to end the violence," he said in Berlin according to news agency DPA. He added that Berlin was also pleased that Israel had had opened a "humanitarian corridor" into the Gaza strip for aid organisations to get through to suffering civilians.