A new criminal offence of illegal working will be announced by David Cameron today as he puts cracking down on immigration once again at the heart of his Government's programme for the new parliament.

In a keynote address ahead of next week's Queen Speech, the Prime Minister will set out the details of a new Immigration Bill, declaring: "We will control and reduce immigration."

Critics will point out how in 2011 he made a "no ifs, not buts" pledge to get net migration to Britain below 100,000; it is now almost 300,000.

Significantly perhaps, the Conservative leader in seeking to take the political initiative on immigration away from Ukip and Labour, does not repeat the previous target number or mention any figure in his address this morning.

The PM will seek to use all the levers of Whitehall to produce a "firm but fair" immigration system, that takes a leaf out of Labour's book on clamping down on unscrupulous employers, who exploit foreign workers by paying low wages thereby undercutting home workers.

The new Bill will build on recent powers, which have resulted in more than 800 foreign criminals being deported under the "deport first appeal later" policy", closed down more than 850 bogus colleges and curtailed illegal working and sham marriages.

It will also include measures to cut migrants' access to public services, crack down on unscrupulous landlords and set up a new labour market enforcement agency to tackle the worst cases of labour market exploitation.

At the same time, the Government aims to reduce demand for migrant labour by ensuring Britons have the right skills and training to fill those jobs currently taken up by migrants while continuing to welcome the brightest and best to the UK.

"A strong country isn't one that pulls up the drawbridge, it is one that controls immigration. Because if you have uncontrolled immigration, you have uncontrolled pressure on public services; and that is a basic issue of fairness," Mr Cameron will declare.

Speaking before he travels to Latvia for the Eastern European Partnership summit, which, in part, will look at how to tackle illegal immigration from that region, he will say that uncontrolled immigration can damage the labour market and push down wages; it results in too many people entering the UK legally but staying illegally.

"The British people want these things sorted," the PM will insist.

"That means... dealing with those who shouldn't be here by rooting out illegal immigrants and bolstering deportations, reforming our immigration and labour market rules so we reduce the demand for skilled migrant labour and crack down on the exploitation of unskilled workers. That starts with making Britain a less attractive place to come and work illegally."