As the United Kingdom's fateful referendum on whether to leave the European Union draws nearer, Prime Minister David Cameron is making his final push to convince voters to reject a "Brexit" - or British exit from the EU.

While the most prominent arguments for and against have centered on the economy, as well as questions of British sovereignty and the EU's eye-watering (and expensive) bureaucracy, some within the Jewish community - particularly in Israel but also in the UK itself - have been weighing what a Brexit would mean for Israel.

While the EU is Israel's largest trading partner, it is also the source of seemingly endless funds being poured into extreme anti-Israel NGOs operating inside the Jewish state, many of whom are singularly dedicated to undermining Israel's sovereignty and delegitimizing the country internationally.

It is that fact which prompted a campaign by Israeli activists encouraging supporters of Israel to vote "Out" come June 23, with activists launching a website and viral video campaign backing a "Brexit", in the hope that losing its second largest state funder after Germany will hamper the European Union's interventionist policies.

But speaking to hundreds of Jews at a charitable dinner in London on Monday night, Cameron insisted a Brexit would in fact be bad for Israel.

"Do yo you want Britain, Israel's greatest friend, in there, opposing boycotts, opposing the campaign for divestment and sacntions?" Cameron asked guests at the Jewish Care annual dinner. "Or do you want us outside the room, powerless to affect the discussion that takes place?"

The referendum on British EU membership takes place this Thursday, June 23.

With just two days to go, polls show the Yes and No votes are neck-and-neck.