US President Donald Trump's decision to recognise Jerusalem as Israel's capital is an "unacceptable crime", Palestinian president Mahmoud Abbas said on Thursday as dozens of protesters were injured in clashes with Israeli forces in the West Bank and Gaza, AP reported.

At a meeting with Jordan's king, Abbas said he rejected the US president's decision and believed America had hurt its credibility in the region.

The Palestinians have been rallying Arab support as they formulate a response, Mr Abbas said, and he had also been in contact with other world leaders.

"Fortunately, there was a positive response from all the countries in the world, from Europe and from Africa and countries close to America that don't support the US," he said. "These all are messages to Trump that what he did is an unacceptable crime."