Iranian state media on Wednesday called the appointment of Mohammed Bin Salman to the position of crown prince and successor to Saudi Arabia's King Salman as a "soft coup".

Saudi Crown Prince Mohammed bin Nayef has been relieved of his post and replaced by Deputy Crown Prince Mohammed bin Salman, a royal decree said on Wednesday, in a promotion for King Salman's 31-year-old son that confirms him as next ruler of the kingdom.

Iran said on Thursday it is ready for talks with Saudi Arabia to promote regional peace despite "unlawful and inflammatory" remarks by the Saudi deputy crown prince, who vowed to protect his kingdom from what he called Iranian efforts to dominate the Muslim world.

Saudi Arabia's powerful deputy crown prince ruled out on Tuesday any dialogue with arch rival Iran and pledged to protect his conservative kingdom from what he called Tehran's efforts to dominate the Muslim world.

Saudi Arabia could launch a land offensive in Yemen to crush its Iranian-aligned Houthi enemies but the cost in casualties would be heavy on both sides, the kingdom's powerful deputy crown prince said on Tuesday.

Iran dismissed as "nonsense" comments made after U.S. Defense Secretary James Mattis met with Saudi Deputy Crown Prince Mohammed bin Salman that condemned Tehran's destabilising regional influence, state news agency IRNA reported on Friday.

Saudi Deputy Crown Prince Mohammed bin Salman left Saudi Arabia on Monday for the United States for a visit scheduled to include talks with U.S. President Donald Trump, the Royal Court said in a statement carried by state news agency SPA.

Oman, which has traditionally resisted Gulf Arab states' efforts to close ranks against Iran, has joined a Saudi-led coalition of Muslim countries to fight terrorism, Saudi and Gulf sources said on Wednesday.

Saudi Arabia's powerful deputy crown prince is due to meet U.N. Secretary-General Ban Ki-moon...

President Barack Obama and the deputy crown prince of Saudi Arabia on Friday discussed ways to support...

U.S. President Barack Obama will meet with Saudi Arabia's powerful deputy crown prince on Friday ...

Saudi Arabia's powerful deputy crown prince held a full day of meetings with U.S. lawmakers on Wednesday...

Saudi Arabia's powerful deputy crown prince flew to the United States on Monday for meetings with U.S. President...

Saudi Arabia's powerful deputy crown prince is expected to visit Washington in mid-June...