RAMALLAH, West Bank, Aug 27 (Noah Browning/Reuters) - Human Rights Watch on Monday rebuked the Palestinian Authority (PA) for failing to prosecute members of the security forces over years of alleged beatings and abuse of protesters, journalists and detainees.

The New York-based group called on the United States and European Union, the major donors to the PA, to reevaluate their security aid, given what it called this record of impunity.

The PA should end its foot-dragging and promptly investigate and prosecute abuse by members of its security forces, said Joe Stork, deputy Middle East director at HRW, in a statement.

The EU and US should take a hard look ... and condition support for those (security) forces on credible investigations and prosecutions of abuses, he added.

The Western-backed Palestinian Authority, which exercises limited self-rule in the Israeli-occupied West Bank, rejected the allegations.

A spokesman for the security forces denied HRW's claim that no personnel had been prosecuted in recent years. Without citing specific cases, he said military courts and the office of the attorney general were pursuing cases of alleged abuse.

We don't believe (HRW) has done a thorough investigation... The PA has greater transparency than Human Rights Watch and the United States, the spokesman, Adnan Damiri, said.

A PA security sweep of officers suspected of corruption and armed criminals has netted dozens of suspects, some of whom have been detained for months awaiting trial, officials say.

Millions of dollars in Western aid and training to PA forces, which coordinate with Israel, have contributed to the relative calm of the West Bank in recent years in what Abbas, the West and Israel regard as a success story.

But critics say the aid props up a government with no electoral mandate or real sovereignty.

Not just the Palestinian security forces, but all agencies of the PA are dependent on international aid. This is a result of the Oslo peace process and when we achieve statehood we would hope to be rid of this situation, Damiri said.

Heavy-handed security methods have been used in the West Bank on occasion.

On two days in late June and early July, uniformed and plainclothes police set upon scores of Palestinian demonstrators marching to the compound of President Mahmoud Abbas in Ramallah to protest against a planned meeting with an Israeli politician.

Several of those present, including a Reuters cameraman, were manhandled, punched and struck with batons, resulting in four arrests, several injuries that required hospital treatment and broad concern among Palestinians at the PA's use of force.

An independent committee of inquiry established by Abbas recommended prosecuting senior Ramallah police officers. The president has been considering the report for about a month. (Reporting By Noah Browning; Editing by Douglas Hamilton and Alistair Lyon)