Jordan's King Abdullah II met Palestinian President Mahmoud Abbas in Amman on Sunday and told him the kingdom was against any Middle East moves that could exclude Palestinians, official media reported.
The meeting came eight days after US President Joe Biden visited the region and met Arab leaders on a visit mainly aimed at repairing strained ties with Gulf nations.
King Abdullah said Jordan was seeking to "reaffirm the centrality of the Palestinian issue", the official Jordanian news agency said.
He said "the Palestinian brethren must be included in regional projects" and "not be marginalised".
Mr Biden met Mr Abbas in Bethlehem on July 15 and pledged $100 million in extra aid to the Palestinians, but did not offer any new peace plan.
A day later he told leaders of the GCC, Jordan, Egypt and Iraq in Jeddah that Washington "would not walk away from the Middle East".
Mr Abbas has a second home in Amman, where he regularly meets King Abdullah.
The king told him last month that Jordan was working to put the Palestinian issue at the top of the agenda for the Jeddah summit.
A large proportion of Jordan's 10 million population are of Palestinian origin. The kingdom signed a peace treaty with Israel in 1994.