The invitation comes as the US administration moves forward with formalising the "Board of Peace" structure linked to Trump's broader Gaza roadmap.
She added that Washington wants to facilitate both the Palestinian Authority and Israel coming together, 'being accountable' and moving forward for peace.
The advance of the Al-Qaeda splinter group the Islamic State in Iraq and Syria and its allies towards Baghdad appears to have been "stalled" but the "grave" situation in Iraq needs to be dealt with militarily as well as politically, a top UN official has said.