Martin Griffiths' office said he is discussing 'concrete steps' with the warring sides to secure a nationwide ceasefire to help counter the threat of novel coronavirus.
The legitimate government is insisting that the Houthis comply with the terms of the Stockholm Agreement before they will continue with peace talks.
The top US diplomat will hold Iran-focused talks with King Salman, Crown Prince Mohammed bin Salman and Foreign Minister Faisal bin Farhan.
The IRGC's Quds Force has been reinforcing the arsenal of its affiliated Iraqi militias with a range of missiles and advanced weapons for months.
Oman's minister of state for foreign affairs Yusuf bin Alawi visited Tehran to discuss 'bilateral relations and regional issues'.
Oman is among those calling for the release of a British-flagged tanker and for London and Tehran to resolve their dispute with diplomacy.
The US president said he called off the strikes because the expected death toll of 150 people would not have been a 'proportionate' response to Tehran shooting down an American drone.
The chair of the Redeployment Co-ordination Committee convened its first meeting by videoconference Wednesday to discuss the general outlines of its work.
UN special envoy to Yemen Martin Griffiths is expected to brief the Security Council Thursday on the outcome of his talks with all parties.
The Dhahran Declaration condemns Iran's 'aggressive attempts to destabilise the security and fuel sectarian sedition in the Arab countries'.