Reza Pahlavi, the exiled son of Iran's former Shah, urged European governments not to appease Iran's leadership, saying continuing to negotiate would only keep the current power system in place.

"If you think you can make peace with this regime, you are sorely mistaken," he said during a press conference in Berlin on Thursday. "There will never be stability, even if a watered-down version of this system survives." 

Europe faces a choice "between a dying regime that endangers us all and a free Iran," the 65-year-old said.

"The regime has never been as fragile as it is now," he added. "It is a wounded beast."

Pahlavi said there were no pragmatists or reformers among Iran's current leaders, saying they were simply "different faces of a regime."

Claiming that 19 political prisoners were executed by Iranian authorities in the past two weeks, he asked if the "free world will do something or watch the slaughter in silence?"

The former Crown prince has put himself forward as someone who could lead a democratic transition in the event that Iran's leadership is toppled.

Pahlavi splashed with tomato sauce by protester

Following his appearance at the federal press conference venue in Germany's government district, Pahlavi was splashed with a red liquid by a protester.

Police detained a man after the incident and said he was being questioned about his identity and motive. The police added that he was not previously known to them.

Initially, authorities described the incident as an attack involving a tomato but later said only that a red liquid had been thrown.  Pahlavi's team said it was tomato sauce.

Why is Reza Pahlavi in Germany?

Pahlavi, who is seen by Iranian monarchists as the leader of Iran's opposition, is in Germany to gather support for his campaign for political change in Iran.

Pahlavi is expected to meet with Armin Laschet, a lawmaker from Chancellor Friedrich Merz's conservative Christian Democratic Union (CDU), as well as foreign policy figures from other parties. But there were no plans for him to meet a member of the government.

When asked why that was, Foreign Minister Johann Wadephul said Pahlavi was coming to Germany as a private individual and was "also engaging in political discussions," but added that it was "not the federal government's role to hold such talks."

During Thursday's press conference, Pahlavi called this "a disgrace." He said democratic governments should "speak with the people who are the voice of the voiceless," and accused Berlin of allowing itself to be blackmailed by the regime in Tehran.

Hundreds of Pahlavi supporters gathered in Berlin to demonstrate for regime change in Iran. There were also counter protests, and Pahlavi was hit by a tomato thrown at him after he left the press conference. 

Could Pahlavi be Iran's next leader?

Laschet, who chairs the Bundestag's foreign policy committee, defended his decision to hold talks with Pahlavi, saying he was "convinced" Pahlavi "can be a person who leads a transition."

"He is the only well-known face of the opposition. And for many Iranians, he is simply the alternative to the mullah regime for now,” the CDU politician told public broadcaster ARD. "He ... sees himself as a transitional figure, not as a permanent ruler, nor as a new Shah." 

If the "regime were to truly fall," Laschet said, "many could rally behind him."

Pahlavi himself said he was confident he had the support of Iranians, and that millions of people had shouted his name on the streets. "They trust me," he said.

However, a change in Iran's leadership has appeared increasingly unlikely, with Tehran showing no sign of backing down after weeks of US-Israeli attacks and a blockade by the US Navy.

Who is Reza Pahlavi?

Pahlavi, who lives in exile in the US state of Maryland, is the eldest son of Iran's last Shah Mohammad Reza Pahlavi, who was deposed in the 1979 Islamic Revolution.

While he enjoys support from monarchists, Pahlavi is seen as a controversial figure among Iran's opposition groups, some of whom reject the idea of a member of the former royal family returning to take power. Critics have accused him of lacking democratic legitimacy and of being too close to Israel.

It's also not clear how much support he has inside Iran.

Edited by: Rob Turner