The Office for National Statistics on Thursday released estimates that 318,000 more people moved to the UK in 2014 than left, a peak not seen since 2005 when net migration was 320,000.
"The ONS figures only prove that people want to come and work here as well as showing how pointless Cameron's ambitious 'tens of thousands' statement was," Jean Lambert said.
Cameron campaigned in this month's election on the promise to reduce annual net migration from outside the European Union to less than 100,000 people. His Conservative Party gained an unexpected majority in the 650-seat House of Commons on May 7.
"Even by the usual standards of anti-immigration rhetoric, it is difficult to see how David Cameron's policy announcements on what he calls 'illegal' immigration will work," Lambert told Sputnik.
In Thursday's speech to unveil a harsh new immigration bill, Cameron pledged to make it more difficult for undocumented migrants to work, study or reside in the UK. The bill includes a new provision to criminalize illegal employment and seize migrants' wages "as proceeds of crime."
In an interview with Sputnik on Friday, Lambert suggested that instead of appearing "tough" with his anti-immigration stance, Cameron could work with local authorities to help them adapt effectively to change.