Iran has been rocked this week by protests that started in Tehran and have spread to other cities, with at least six people killed in clashes with security forces.

Official media has largely played down the protests but videos have flooded social media, many of which are difficult to authenticate, or have even been manipulated.

Here is a recap of what we know and what analysts think it all means.

- What's going on? -

The protests began on Sunday in Tehran, where some shopkeepers went on strike over high prices and economic stagnation.

Jan 2 (Reuters) - Yemen's southern separatist movement said on Friday it aims to hold a referendum on independence from the north in two years following its seizure of swathes of the country last month in a move that triggered a major feud between Gulf powers.

The Southern Transitional Council (STC) is backed by the United Arab Emirates and has for years been part of Yemen's internationally recognised government which is supported by Saudi Arabia and has led the fight against the Houthi movement.

ROME, Jan 2 (Reuters) - Emanuele Galeppini, a 16-year-old Italian international golfer who lived in Dubai, was named on Friday as the first of several possible victims from Italy to be identified after a New Year's Eve bar fire in the Swiss ski resort of Crans-Montana.

"The Italian Golf Federation mourns the passing of Emanuele Galeppini, a young athlete who carried with him passion and genuine values," the federation said in a statement.

ANKARA, Jan 2 (Reuters) - Turkish President Tayyip Erdogan said he would have a phone call with U.S. President Donald Trump on Monday to discuss peace efforts between Ukraine and Russia as well as issues surrounding Gaza.

Speaking to reporters in Istanbul on Friday, Erdogan also said Turkey's Foreign Minister Hakan Fidan will attend a meeting of the "Coalition of the Willing", a group of nations backing Ukraine, in Paris in coming days.

(Reporting by Huseyin Hayatsever; Editing by Jonathan Spicer )

By Yousef Saba

DUBAI, Jan 2 (Reuters) - Yemen's more than decade-long civil war has flared up after a United Arab Emirates-backed separatist movement swept through territory in the south, splintering the Saudi-led coalition that was created to fight the Iran-aligned Houthi group.

Below are details of the key factions in the conflict in Yemen, which has caused one of the world's worst humanitarian crises:

THE HOUTHIS

President Donald Trump said on Friday that the United States was "locked and loaded" to respond if Iran killed protesters, prompting Tehran to warn that intervention would destabilise the region.

Protesters and security forces clashed in several Iranian cities on Thursday, with six people reported killed, the first deaths since the unrest escalated.

Shopkeepers in the capital Tehran went on strike on Sunday over high prices and economic stagnation, actions that have since spread into a protest movement that has swept into other parts of the country.

DUBAI, Jan 2 (Reuters) - U.S. President Donald Trump threatened on Friday to come to the aid of protesters in Iran if security forces fire on them, days into unrest that has left several dead and posed the biggest internal threat to Iranian authorities in years.

"We are locked and loaded and ready to go," he said in a social media post. The United States struck Iranian nuclear facilities in June, joining an Israeli air campaign that targeted Tehran's atomic programme and military leadership.

Yemen's UAE-backed separatists announced a two-year transition to independence Friday despite reporting 20 deaths in airstrikes from a Saudi-led coalition trying to roll back their weeks-long offensive across the country's south.

A separatist military official and medical sources reported 20 fighters dead in air raids on two military bases as the coalition also targeted an airport and other sites.

Jan 2 (Reuters) - U.S. President Donald Trump on Friday said that if Iran shoots and violently kills peaceful protesters, the United States of America will come to their rescue.

"We are locked and loaded and ready to go," he said in a Truth Social post.

This follows the deaths of several people as Iran's biggest protests in three years over economic hardship turned violent across multiple provinces.

DUBAI, Jan 2 (Reuters) - Saudi Arabia's ambassador to Yemen said on Friday that Aidarus Al-Zubaidi, the leader of the UAE-backed Southern Transitional Council (STC), refused landing permission the previous day for a plane carrying a Saudi delegation to Aden.

The halt in flights at Aden international airport was the latest sign of a deepening crisis between Gulf powers Saudi Arabia and the United Arab Emirates, whose rivalry is reshaping war-torn Yemen.