TEHRAN, Young Journalists Club (YJC) -Martin Griffiths is set to meet with Yemen's Huthis, who control the capital along with the Red Sea city of Hodeida, home to the country's most valuable port.
He did not make a statement upon his arrival at the Yemeni capital's international airport.
Two weeks of UN-brokered talks have not yet found a solution to the government offensive on Hodeida, backed by the United Arab Emirates and its allies in a Saudi-led regional coalition supporting President Abedrabbo Mansour Hadi, AFP reported.
The Hodeida offensive has raised fears of for civilians in Yemen.
The United Arab Emirates said Sunday it had halted the offensive to give a chance to UN diplomatic efforts.
Hodeida port is the entry port for some 70 percent of imports to Yemen, where eight million people face imminent famine.
Both the UAE and the Hadi government have held firm to their rejection of anything short of a full Huthi withdrawal.
Griffiths has said a proposal to grant the UN a major role in managing the port was being studied.
The UN envoy met with Hadi in the southern city of Aden on Wednesday and is reported to be pushing for the Huthis to cede control of Hodeida to the United Nations.
The United Nations has called Yemen the world's largest humanitarian crisis.