"...We could never guarantee how the intelligence might or would be used by the state of Israel.."

British intelligence wasn't always forthcoming with sharing information with its Israeli counterpart, former MI6 director Sir Richard Dearlove said in a conference Wednesday, adding that he felt Israeli intelligence played by a different set of rules than the U.K. agency.

Dearlove, the British spy chief from 1999 to 2004, said in a conference marking 60 years of British-Israeli diplomatic relations that he had "no doubt that Israel plays by a different set of rules ... I'm not going to expand on that, but I will just have to leave it to the imagination," Dearlove added, saying that he had frequent discussions "with Robin Cook as Foreign Secretary about what should or shouldn't be passed to our Israeli colleagues - and there are obvious reasons for that, because we could never guarantee how the intelligence might or would be used by the state of Israel."

However, the former U.K. spy chief also stressed the strategic importance of British ties with Jerusalem, saying that while the "relationship with Israel is difficult," that did not mean that "it's not important and that it's not given close attention professionally and politically."

Dearlove expanded on the cooperation between the two countries on Iran, saying it was an "immensely important" link. "Of course it does overflow into the role of Hamas and Hizbollah, both of which are largely, in terms of the way they behave towards Israel, Iranian surrogates," the former MI6 chief added..."