Technology developed by two leading Israeli software companies is thought to have been used in the American National Security Agency’s (NSA) Prism surveillance programme and other data-collecting schemes that were exposed in the international press last weekend.

According to various American publications, the two main Israeli companies to have supplied software used by the NSA and other US electronic intelligence agencies are Narus and Verint.

Narus was founded in 1997 in Israel but was bought by the Boeing Corporation in 2010. It has been alleged that Narus was a main contractor in a surveillance operation carried out in collaboration with the AT&T telephone company.

Verint, the owners of Israeli software giant Comverse, was allegedly involved in the surveillance of Verizon mobile phone users.

Many of their founders and original engineers of both Israeli companies served in the IDF’s information technology units and its main electronic intelligence department, Unit 8200. Senior managers in both firms have said in the past that their technology has been used by Israeli intelligence.

Another Israeli connection to the NSA operations is through the instant messaging service, PalTalk, one of the American communications companies reported to have allowed the Prism programme to collect information from its servers. For over a decade, PalTalk has used VoIP (Voice-over Internet Protocol) technology developed by Deltathree, an Israeli company now based in New York.

The companies and authorities involved refused to comment on Israeli connections to the American intelligence programmes.

However, Unit 8200, as well as other Israeli intelligence agencies, are known to have a close working relationship with their American counterparts. Unit 8200 also collaborates closely with Britain’s electronic intelligence-gathering organisation, GCHQ.

Senior Israeli intelligence officials said recently that “intelligence sharing between Israel and Britain on matters including Iran and Syria has never been better”.

In Israel, electronic surveillance of Israeli citizens is carried out by the police, and in cases involving national security issues it is done on behalf of the Shin Bet. Each wiretap needs to be authorised by a judge.

According to reports in the New York Times published last year, Israeli and American intelligence co-operated in the “Olympic Games” cyber operation directed at the Iranian nuclear programme.

The project resulted in the Stuxnet malware which sabotaged the centrifuges that enriched uranium for Iran’s planned nuclear weapon.