A deal has been reached between Israeli and Palestinian negotiators to extend US-brokered peace talks, according to Middle Eastern news outlet Al-Arabiya.

As part of the deal, Israeli spy Jonathan Pollard is to be freed from his 27-year detention in the US while the contentious fourth set of Palestinian prisoners are to be released.

The American-born Pollard was sentenced to life in 1987 after admitting to passing on US miliary secrets to the Jewish state whilst working as civilian intelligence analyst for the US Navy.

The negotiations were on the verge of breakdown after Israel refused to release the Palestinian prisoners and, in retaliation, Palestinian Authority President Mahmoud Abbas registered with 15 UN agencies against Israel's wishes.

The new deal will see Israel release an unknown number of Palestinian prisoners and suspend settlement construction in the West Bank.

In return, the Palestinians will suspend their plans to join the UN bodies, including the Geneva Convention on the conduct of war and occupations.

Abbas said he signed letters of accessions to 15 international conventions, thus bolstering Palestine claims to statehood, in response to Israel's failure to release the prisoners.

Kerry previously said that both sides had taken "unhelpful, unilateral actions".

"This is not an open-ended effort, it never has been," Kerry said. "It is reality check time, and we intend to evaluate precisely what the next steps will be."

"Both parties say they want to continue, neither party has said they want to call it off, but we're not going to sit there indefinitely," he said.

The US had hoped to reach an agreement by 29 April but this date seems to have given more time for a deal to be reached. The new deadline date is as yet unknown.