"Tunisia's ambassador to the United Nations has been dismissed for purely professional reasons concerning his weak performance and lack of coordination with the ministry on important matters under discussion at the UN," a foreign ministry statement said.
Diplomatic sources believe that Ambassador Moncef Baati, who has occupied a seat at the UN Security Council since the start of the year, had gone further than President Kais Saied wanted in his criticism of Trump's long-delayed peace plan.
Saied, a political outsider who took office in November after a surprise election victory, was concerned that Baati's expressions of support for the Palestinians risked damaging Tunisia's relations with the US, the sources said.
"It was quite a shock to hear that. I don't know all the details, the reason behind this," Ambassador Marc Pecsteen de Buytswerve of Belgium, which holds the rotating presidency of the Security Council, said of the firing.
"He was a very good colleague and I really very much regret to see him leave," he added.
Another diplomat and member of the Security Council, who did not wish to be identified, said Baati was "the right person" to negotiate a resolution wanted by the Palestinians.
Baati's swift recall to Tunis meant that he missed a closed-door briefing to the Security Council on Thursday by the US plan's architect, Trump adviser and son-in-law Jared Kushner.
The US plan proposes to allow Israel to annex all its illegal settlements as well as the strategic Jordan Valley. The Palestinian Authority (PA) government wants an independent state in the West Bank, the Gaza Strip and East Jerusalem - territories seized by Israel in the 1967 war.
After the briefing, Kushner blamed PA President Mahmoud Abbas for a spike in violence in Israel and the occupied Palestinian territories since the plan was unveiled on January 28.
Abbas "calls for days of rage in response and he said that even before he saw the plan," Kushner told reporters in New York.
Abbas is due at the UN next week to oppose the plan and demand adherence to international law.
The Palestinian leadership hopes to push for a Security Council resolution condemning the Trump plan, but any text will almost certainly be vetoed by the US.
A veteran diplomat, Baati was in retirement last year when he was asked to return to active duty and represent Tunisia at the UN.
Be Part of Quality Journalism
Quality journalism takes a lot of time, money and hard work to produce and despite all the hardships we still do it. Our reporters and editors are working overtime in Kashmir and beyond to cover what you care about, break big stories, and expose injustices that can change lives. Today more people are reading Kashmir Observer than ever, but only a handful are paying while advertising revenues are falling fast.