UK = A report from the Home Affairs Committee said: "Past experience has shown that previous attempts to tighten immigration rules have led to a spike in immigration prior to the rules coming into force. "Much will depend on the negotiations between the UK and the EU and the details of any deal to retain or constrain the free in the European Union." It suggested three “cut off” dates for when EU citizens can apply for permanent UK residence: the June 23 referendum, the date Article 50 is triggered to begin Brexit talks or the day Britain actually leaves the bloc. Mr Vaz said: "There is a clear lack of certainty in the Government's approach to the position of EU migrants resident in the UK and British citizens living in the EU...One in three lorries arriving in Britain do not have the security measures needed to keep out stowaways, border officials have also found as it emerged almost half of all people smuggling fines are never paid. Around 750,000 vehicles a year come to the UK without the necessary locks on doors and other measures needed to make sure illegal migrants cannot ride across the border undetected, according to the Border Force. Millions of pounds of penalties for people smuggling have also gone unpaid in recent years after thousands of foreign drivers were caught but failed to pay up.