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Tunisians also called on their government to criminalise any form of normalisation or co-operation with Israel, even through unofficial channels.
The protesters chanted slogans calling for Arab unity and condemning perceived western complicity in war crimes and what they said was the whitewashing of breaches of international humanitarian law committed against the people of Gaza.
“Unity, unity of all Arabs against the Zionist attack,” and “the people want to liberate Palestine”, they shouted.
Demonstrators yelled anti-French and anti-US slogans as the march reached the French embassy in central Tunis.
“French and Americans, partners in the aggression,” they shouted.
“The slightest level of faith tells us to at least speak up for them [Palestinians] while they are fighting there for their struggle," Moncef, 64, told The National.
"We kiss their foreheads and we tell them that we wish we were there to at least take a little of that burden that you carry on your shoulders."
Malik Kammoun, an MP who attended the rally, said legislators were speeding up the discussion and passing of a bill to criminalise any form of normalisation with Israel.
"It is crucial for us today to issue a law that affirms our stance against any current or future recognition of what is called the state of Israel,” Mr Kammoun told The National.
Thousands of civilians have been killed on both sides after fighters from the Gaza-based Palestinian militant group Hamas attacked Israelis across the border on Saturday and Israel launched air strikes on Gaza in retaliation.
“Tunisia adheres to the right of the Palestinian people to establish their independent state on all of the land of Palestine, with its capital being the holy city of Jerusalem,” the Tunisian presidency wrote on its Facebook page.
The statement came after an emergency meeting of Arab League foreign ministers in Cairo that called for an immediate halt of Israel's bombardment of the Gaza Strip and warned the violence could spiral out of control.
Tunisia's pro-Palestine stance is in alignment with the country's general public sentiment. Previous governments have maintained a position of support for a two-state solution to the Israeli-Palestinian conflict.
Hama Hammami, leader of the opposition Workers Party, told The National that Israeli aggression on Palestine "is not new to Israel but this battle is an important shift in the history of Palestinian resistance and a normal development for any liberation movement in the world”.
He said it was not enough for the Tunisian government to release statements and it should put pressure on the western world through every means available.
“What are we doing in Nato as an exceptional partner?" he said. "We have to leave. We should also pull out from any agreement that gives space for Israel in order to isolate it."