EU Referendum highlighting divisions within the Conservative Party in the UK, with backbench MP's warning David Cameron

The transcript discusses the prominence of immigration in the EU referendum campaign, highlighting concerns about border security and the impact of immigration on public trust. Boris Johnson criticizes David Cameron for failing to meet immigration targets, arguing that leaving the EU is necessary to control borders. The Conservative Party faces internal divisions, with Cameron's leadership under threat. Labour MPs claim the Tory leadership challenge is damaging the referendum debate, accusing the Leave campaign of scaremongering on immigration. The immigration debate is expected to intensify leading up to the referendum.

What impact does the Tory Leadership Challenge have on the referendum debate according to senior Labour MPs?

What is suggested about the immigration argument as the referendum date approaches?