GAZA, Jan 28 (Nidal Al-Mughrabi\Reuters) - Thousands of protesters took to the streets of the West Bank and Gaza on Friday to voice support and opposition to Palestinian President Mahmoud Abbas in rallies that underlined the deep divisions between the two territories.

In Gaza, which is run by the Islamist group Hamas, demonstrators demanded the prosecution of Abbas following the publication of leaked documents this week showing his negotiating team had offered peace concessions to the Israelis.

In the West Bank, which is run by Abbas's Palestinian Authority (PA), supporters vowed allegiance to their president.

We sacrifice our souls and blood for you, a crowd chanted in Ramallah after Abbas had attended Friday prayers in a city-centre mosque that was once a Hamas stronghold.

Hamas won the last Palestinian legislative elections, held in 2006, and seized control of the Gaza Strip in 2007 after a brief war with forces loyal to Abbas. It refuses to recognise Israel and has denounced attempts to negotiate a peace deal.

Al Jazeera stunned many Palestinians this week when it leaked hundreds of confidential minutes documenting more than a decade of peace talks between the PA and Israeli officials.

The papers show Abbas's team offering big concessions in core areas such as the borders of a future state, the fate of Jerusalem and the rights of return of refugees to their home towns and villages in modern-day Israel.

Senior Hamas leaders said their group would seek the prosecution of officials involved in the peace negotiations.

The (PA) has offered up concessions and has been involved in every political crime that harmed our people, said Hamas leader Khalil Al-Hayya.

The Palestinian Authority has accused Al Jazeera and Qatar, the Gulf emirate where it is based, of launching a campaign to undermine their leadership, and has questioned both the timing and the authenticity of the broadcast documents.

In Ramallah protesters burnt posters of Hamas'a political chief Khaled Meshaal, the Qatari prime minister and the Iranian President Mahmoud Ahmadinejad.

By contrast, in Jabaliya in the northern Gaza Strip, protesters held aloft posters of the Qatari leader but burnt an effigy of Abbas.

The Palestinian Authorities made clear their disdain for Hamas in the Al Jazeera documents and analysts have said the leaked papers have made reconciliation between the two groups less likely than ever. (additional reporting by Ali Sawafta in Ramallah; editing by Crispian Balmer and Matthew Jones)