BEIRUT, Aug. 16 (Xinhua) -- Supporters of Lebanese Prime Minister-designate Saad Hariri blocked streets in capital Beirut Thursday evening in protest against an interview attacking him.

Salem Zahran, a well-known journalist in the country, said in an interview broadcasted on local TV channel MTV a day earlier that Hariri will have to go to Syria if Saudi Crown Prince Mohammed bin Salman asked him to do so.

Hariri announced before that he refuses to visit Syria or meet with Syrian President Bashar al-Assad under any circumstances, even if that would cost him his position.

"It is impossible that I visit Syria, not now and not in the future. If Lebanon's interest requires so, then you could find someone else," Hariri said after a meeting with his party, the Future Movement, on July 31.

Hariri, a long-time supporter of the Syrian opposition, has often outspoken his desire to see Assad stepping down from power.