Iran is prepared for dialogue if Saudi Arabia is also ready, Iranian Foreign Minister Mohammad Javad Zarif said Wednesday, according to the IRIB news agency.

Tensions have spiked between Iran and Saudi Arabia, arch-rivals for predominance in the Middle East, since Riyadh accused the Islamic Republic of carrying out attacks that damaged six oil tankers in the Gulf, an allegation Tehran has denied.

"If Saudi Arabia is ready for dialogue, we are always ready for dialogue with our neighbors," Zarif said.

"We have never closed the door to dialogue with our neighbors and we will never close the door to dialogue with our neighbors."

The attacks on the oil tankers came as the United States, Saudi Arabia's major big power ally, toughened sanctions on Iran in a bid to force it into negotiations on stricter limits to its nuclear activity and curbs on its ballistic missile program.