US Secretary of State Condoleezza Rice has arrived in Egypt at the start of a five-day Middle East tour.
Condoleezza Rice has a host of issues to discuss with Arab allies
Before setting off, Ms Rice criticised Iran as a "destabilising influence in the Middle East".
Tehran insists the presence of US-led forces in Iraq is the real cause of instability in the region.
BBC Washington correspondent Jonathan Beale says Ms Rice will want US allies in the Arab world to clamp down on militant groups that support Iran.
She also wants Arab allies to maintain pressure on Tehran over its nuclear programme.
A request for more practical Arab support to help bring stability to Iraq is expected to feature on the trip, which also takes in the United Arab Emirates.
In Egypt, the subject of Washington's criticism of the pace of democratic reform may also be broached, after Ms Rice objected to Cairo's decision to delay upcoming local elections.
Another major theme of the trip will be Washington's firm line regarding the militant group Hamas, which won the Palestinian parliamentary election in January.
Ms Rice will urge Egypt and Saudi Arabia not to support a Palestinian government headed by Hamas, which the US, Europe and Israel consider a terrorist organisation.
"I would hope that any state that is considering funding a Hamas-led government would think about the implications of that for the Middle East and for the Middle East peace process," she said last week.
The US and Europe have already announced they will not provide funding directly to the government, and Israel has suspended the monthly payment of tax and customs duties owed to the Palestinian Authority.
Arab League foreign ministers met on Monday to discuss filling the funding gap for the already cash-strapped Palestinian Authority.
They want to revive a funding plan agreed on in 2002 that would provide about $50m a month.
Egypt's banned-but-tolerated Muslim Brotherhood movement has announced an international fund-raising campaign to support the new Palestinian government.