The Arab League has backed Palestinian President Mahmoud Abbas's rejection of Israel as a "Jewish state", as US-backed negotiations approach a deadline next month.

League chief Nabil Elaraby called on Arab countries to take a "firm stand" against Israel's demands, calling it a deviation from an agreed-upon framework for peace talks.

El-Araby delivered his remarks on Sunday as Arab foreign ministers extended their support for the Palestinian leadership at a meeting in Cairo.

[The Arab League] emphasises its rejection of recognising Israel as a 'Jewish state' Arab foreign ministers

"The council of the Arab League confirms its support for the Palestinian leadership in its effort to end the Israeli occupation over Palestinian lands, and emphasises its rejection of recognising Israel as a 'Jewish state'," Arab foreign ministers said in a statement in Cairo.

Abbas had earlier complained that Palestinians were being asked for something that had not been demanded of Arab countries that have previously signed peace treaties with Israel.

"We recognised Israel in mutual recognition in the Oslo agreement, why do they now ask us to recognise the Jewishness of the state?" he asked.

"Why didn't they present this demand to Jordan or Egypt when they signed a peace agreement with them?" Abbas added.

Abbas has said he will never recognise Israel as a Jewish state.

Israeli demands

Palestinians fear the demand is an attempt to restrict possible return options for Palestinian refugees and will lead to discrimination against Israel's sizeable Arab minority, while Israelis say it recognises Jewish history and rights on the land and will signal the Palestinians are serious about peace.

Benjamin Netanyahu has been pushing to make recognition of Israel as a Jewish state a requirement for peace, overshadowing borders, refugees and the status of Jerusalem.

On Tuesday, Netanyahu told pro-Israeli lobby group AIPAC "In recognising the Jewish state you [Palestinians] would finally make clear that you are truly prepared to end the conflict.

"So recognise the Jewish state, no excuses, no delays."

El-Araby described the demand as an Israeli attempt to foil the talks, calling for a reevaluation of the negotiation track.

US Secretary of State John Kerry has been hoping to get the two sides to agree on some general points, including the "Jewish state" and a rough understanding on borders.

Kerry wants Abbas to make concessions as part of efforts to reach a "framework agreement" that could lead to the prolongation of the talks, which have achieved little since they began seven months ago.