Labour's failure to impose an upper limit on immigration is deeply irresponsible, Michael Howard has claimed.

In an article for the Times newspaper, the Conservative Party leader accuses the prime minister of losing control of the issue, with "tragic consequences" for immigrants.

He cites the case of the Chinese cockle-pickers who died at Morecambe Bay as an example.

"The deaths of Chinese men and women packed into a lorry at Dover and swept away in the seas of Morecambe Bay have shown just how inhumane our system is," he writes.

"It would be deeply irresponsible not to argue for change when the status quo means perpetuating human misery."