British Prime Minister Theresa May told Israeli counterpart Benjamin Netanyahu on Wednesday that London is "concerned" about Palestinian deaths on the Gaza border, as he insisted the protests were driven by Hamas.

As the pair met at her Downing Street office, they were at odds over the clashes on the Gaza Strip border fence.

May said Britain was "concerned about the loss of Palestinian lives" in the recent Gaza protests.

She said Britain "absolutely recognises" Israel's right to defend itself against "extremists and terrorists".

"But with 100 Palestinian lives lost and a deteriorating situation in Gaza I hope we can talk about how we can alleviate that situation and how we can ensure that we can get back to a position where we are able to find a way through to talk about a two-state solution."

Netanyahu insisted that the protesters were being "paid for and pushed by Hamas" to try to break through the border and kill Israelis.

"This is not a non-violent protest -- quite the contrary," he said.

"We are doing everything we can to both minimise casualties and at the same time protect Israeli lives."

Britain considers Hamas, which has run the Gaza Strip since 2006, as a terror organisation.

Since March 30, Gazans have been holding border protests demanding the return of Palestinians to land they fled or were expelled from during the 1948 war surrounding Israel's creation, now inside the Jewish state.

The demonstrations are accompanied by smaller clashes as youths hurl stones at Israeli soldiers and attempt to breach the border fence, at times laying explosive devices on the fence or throwing grenades.

At least 125 Palestinians have been killed by Israeli gunfire on the border since March 30.

May also underlined her support for the Iran nuclear deal after President Donald Trump last month pulled the United States out of the accord -- a move applauded by Iran's arch-foe Israel.

Netanyahu is on a European tour where he has tried to convince leaders to follow Trump's stance.

He told May he was focused on making sure Iran did not get a nuclear weapon, and on "how to roll back Iran's aggression in the region".

But May said: "Along with France and Germany the UK continues to believe that is the best route to preventing Iran from getting a nuclear weapon.

"We will remain committed to it as long as Iran meets its obligations.

"But we do recognise that there are other issues that need to be addressed in relation to Iran -- its destabilising regional activity in countries like Syria and Yemen and also the the proliferation of ballistic missiles," she said.