Doctors wanting to work for the NHS will have to prove they are fluent in English if proposals go ahead.
Experts will consult over the next few months on the plan put forward by Health Secretary Andrew Lansley.
The move comes after the case of Daniel Ubani, a German locum doctor who gave a 70-year-old patient a fatal painkiller overdose on his first and only shift in Britain in February 2008.
Currently only doctors from outside the EU must take rigorous language tests.
European laws make it illegal to systematically test EU doctors when they register.
This means examples of poor language skills can sometimes slip through the net and put patient safety at risk.
Under the new proposals senior doctors who evaluate other doctors' fitness to practice would have extra powers to ensure that any doctor working for the NHS can speak English.
These Responsible Officers, of which there are 500 in England, would work with the regulatory body the General Medical Council to ensure doctors have undergone all the right checks including making sure they understand how the NHS works and the medicines it provides.
Launching the consultation Mr Lansley said: "Sadly, we are all too familiar with what can happen when qualified doctors don't have a good command of English. This puts patients at risk and I am determined to stop this.
"By giving new powers to Responsible Officers we can make sure that doctors not only speak English before they treat patients in this country but are also competent to work within the NHS, making sure that they understand NHS processes and medicines which is as important as language to the quality of care patients receive. I hope everyone gets involved and has their say."
Niall Dickson, chief executive of the General Medical Council, said: "This is a vital issue for patients - they must be able to have confidence that the doctor who treats them has the communication skills needed for the job."