German exports to Iran fell by nearly half in the first six months of 2019, data showed on Monday, suggesting companies are scaling back business ties with Tehran to avoid trouble with the United States after Washington reimposed sanctions.

Iran on Thursday hit out at Bahrain for hosting a "provocative" conference on Gulf maritime security and for its "anti-Iran" rhetoric accusing Tehran of attacking tankers in sensitive waters.

A report issued by World Resources Institute said that nearly a quarter of the world's population living in 17 countries, including India, Saudi Arabia, Pakistan and Libya, are facing extremely high water stress, close to "day zero".

British Prime Minister Boris Johnson confirmed in a phone call with King Hamad bin Isa Al Khalifa UK's commitment to the Iran nuclear deal.

Britain on Monday joined the United States in a maritime security mission in the Gulf to protect merchant vessels travelling through the Strait of Hormuz after Iran seized a British-flagged vessel.

Bahrain Interior Minister Rashid bin Abdullah Al Khalifa reiterated his country's accusations to Iran and Qatar of "promoting chaos" in Bahrain which has been witnessing protests demanding political reform since 8 years.

President Hassan Rouhani said on Thursday that Iran was ready for the worst in an uphill struggle to salvage its nuclear deal with world powers abandoned by the United States, but that he was sure Tehran would eventually prevail.

Bahrain hosted a conference on Gulf maritime security on Wednesday, after multiple attacks on shipping in the strategic Strait of Hormuz sent tensions soaring between Iran and the US.

The United States on Wednesday imposed sanctions on Iranian Foreign Minister Mohammad Javad Zarif, targeting the country's top spokesman and potentially hurting chances of diplomatic talks amid rising tensions between the two countries.

Germany will not participate in a U.S.-led naval mission to secure the Strait of Hormuz, close to Iran, Foreign Minister Heiko Maas said on Wednesday.

Iran is prepared for dialogue if Saudi Arabia is also ready, Iranian Foreign Minister Mohammad Javad Zarif was quoted as saying on Wednesday.

Iranian Supreme Leader Ayatollah Ali Khamenei said on Wednesday the will of the people would prevail in Bahrain after protests there following the execution of two Shi'ite Muslim Bahraini activists over the weekend.

Iran was to revive maritime security talks on Tuesday with traditional foe the United Arab Emirates (UAE) in an apparent bid to calm tensions in the Gulf, although a Gulf official described the discussions as routine and technical.

Iran has strongly condemned the execution in Bahrain of two Shia Muslim men convicted of terrorism, saying the Gulf state's crackdown on dissent was bound to fail, reported AFP.

An American website said that the USS Boxer pulled into Bahrain's Khalifa bin Salman Port on Thursday for a visit, days after the amphibious assault ship made headlines for downing at least one Iranian drone in the Strait of Hormuz.

U.S. Secretary of State Mike Pompeo said on Thursday he was willing to go to Iran for talks amid tensions between Tehran and Washington, but also called on Japan, Britain and other nations to join a maritime force to guard oil tankers sailing through the Strait of Hormuz.

Britain has started sending a warship to accompany all British-flagged vessels through the Strait of Hormuz, a change in policy announced on Thursday after the government previously said it did not have resources to do so.

No Iranian drone has been brought down, the ISNA news agency quoted Iran's Defense Minister Amir Hatami on Wednesday as saying, after the U.S. military said it taken action against two Iranian drones in the past week.

Qatar-based Al Jazeera TV on Wednesday quoted the military adviser to Iran's supreme leader as saying that any change in the status of the Strait of Hormuz, which Tehran says it protects, would open the door to a dangerous confrontation.

Iran will secure the Strait of Hormuz and not allow any disturbance in shipping in the key oil transport waterway, Iranian Deputy Foreign Minister Abbas Araqchi said on Tuesday during a visit to Paris, the state new agency IRNA reported.