A change in the law that will allow terminally ill people to be helped to end their lives is inevitable and will happen within as little as a couple of years, according to the deputy chair of the British Medical Association (BMA).

Speaking in a personal capacity, Dr Kailash Chand has thrown his weight behind Lord Falconer’s private member’s bill, which would offer assisted dying to terminally ill patients who are deemed mentally capable and are likely to have less than six months to live.

On Friday, the House of Lords voted unanimously to accept an amendment to the assisted dying bill, tabled by Lord Pannick and supported by Falconer, that would see all applications for assisted death subject to judicial oversight.

The move was welcomed by campaigners as a major step in changing the law. Chand said it was clear that momentum was now swinging behind those pushing for reform.

“No change is not an option,” he told the Observer. “The present law definitely needs changing. It discriminates and is very bad law. We currently have a two-tier system – one for the people who have the resources and money to go to the Dignitas clinic in Switzerland and another for the majority of people who don’t have the resources or money.”

Some peers worry that disabled and vulnerable people will be pressured into ending their lives if the law is changed Several religious groups are opposed to the measure. The BMA, which represents Britain’s doctors, also fiercely rejects moves to legalise assisted dying.

However, Chand implied that the organisation was out of step with the public. “Look at the surveys. Between 60% and 70% of the public are in favour of a change in the law. Three-quarters of nurses are in favour. Only the doctors’ community is not substantially in favour. But if you ask a doctor a personal question whether, if they were in that sort of situation, would they want it, their answer would be yes.”

In a move that is likely to anger opponents, Chand called for a change in the language used in relation to the issue. “I don’t call it euthanasia or assisted dying; I call it dying with dignity. If we are allowed to live with dignity, why should we not be allowed to die with it?”

He also dismissed arguments that advances in palliative care meant many terminally ill people could now enjoy their final days. Examples of people who came round after asking not to be revived and went on to live for many more weeks or months were also misleading, Chand said. “Of course, you can find examples of these people who are still around, but those are very few exceptions.”

Right-to-die campaigners hailed Friday’s vote in the Lords as a breakthrough. The agreed amendment would require a judge in the family division of the high court to confirm that a terminally ill patient with less than six months to live had reached “a voluntary, clear, settled and informed” decision to control the time and manner of their death.

“We have moved a significant step closer to a change in the law,” said Sarah Wootton, chief executive of Dignity in Dying. “Reacting to pressure from the public and the courts, the House of Lords have accepted the principle of change and identified a uniquely British model of providing both greater choice and greater protection at the end of life.”

Safeguards such as the involvement of a judge would help ensure that vulnerable people were not pressured into ending their lives, Chand said.

“Things are moving very fast: within two to three years we will definitely see a change in the law. Why are we trying to prolong unnecessary life? Today in the House of Lords we are seeing a battle between those who are seeking a constructive way forward and those who, rather than identifying appropriate safeguards, are seeking to place barriers in the way of dying people having control over their death. Whether the law should change seems to have been settled. It is about how the law changes.”