Home Office Minister James Brokenshire said the government had been "blown off course by net migration from within the EU, which has more than doubled since 2010".
"We have also been constrained in government by Liberal Democrats who don't have that same aim and focus on reducing net migration," he added.
Labour's shadow home secretary Yvette Cooper told BBC News: "No wonder people don't have trust in the immigration system when they have these kinds of promises being broken."