A chief executive has welcomed the announcement of new waiting times in mental health services.

Most people with depression who need talking therapies will begin treatment within six weeks while accident and emergency units will be made to give suicidal patients the same priority as those with suspected heart attacks, said the deputy Prime Minister.

Young people hit by psychosis for the first time should be seen within two weeks - the same target as cancer patients - when the changes come into force next April.

Nick Clegg told activists at the Liberal Democrat party conference in Glasgow the £120m plan is the first step in reforming 'Cinderella' mental health services.

Michael Scott, chief executive of Norfolk and Suffolk NHS Foundation Trust, welcomed the announcement as a positive step but sounded a note of caution about the need for improved funding for mental health services.

He said: 'This announcement helps put mental health on more of an even footing with NHS services for physical health but we know that funding for mental health has been falling over recent years. The introduction of new waiting time standards will help improve services and, hopefully, bring greater clarity about the need for fairer funding for NHS mental health services.'

Liberal Democrats would look extend reforms to other areas, such as bipolar and eating disorders, in a future government using half of the extra £1bn that would be raised from tax measures hitting the wealthiest that they would plough into the NHS.

Mr Clegg said: 'For the first time ever, we will introduce national waiting times for patients with mental health conditions.

'Labour introduced waiting times in physical health - we will do the same for the many people struggling with conditions that you often can't see, that we often don't talk about, but which are just as serious.

'So if you are waiting for talking therapies to help with your depression, you will be seen within six weeks - 18 weeks at an absolute maximum - just as if you are waiting for an operation on your hip.

'If you are a young person experiencing psychosis for the first time, you will be seen within two weeks, something we are going to roll out across the country - just as if you suspect you have cancer.

'If you are having a breakdown, if you are thinking of harming yourself, for any emergency which takes you to A&E, you'll get the help you need - just as if you had gone to hospital with chest pains or following an accident.

'These are big, big changes. And in government again the Liberal Democrats will commit to completing this overhaul of our mental health services, ending the discrimination against mental health for good.

'And while I know not everyone in the party is going to agree, I can tell you now, I want this smack bang on the front page of our next manifesto.'

Mental health problems are estimated to cost the economy around £100bn a year and around 70m working days are also lost annually.

Simon Stevens, NHS England's chief executive, said: 'This is an important moment when we will bring parity of esteem for mental health services a step closer. Putting access and waiting standards in place across all mental health services, and delivering better integration of physical and mental health care by 2020, will bring us much closer towards that aim.'

Dr Geraldine Strathdee, NHS England's national clinical director for mental health, said: 'This programme will start the journey to transform mental health care in England. Today people who present in crisis often wait too long for an assessment and to access treatment.

'This new approach will help improve crisis care and help reduce the distress that untreated mental illness brings. With 75% of long term mental health problems diagnosed before 18, investing in early effective treatments will pay immediate and long-term dividends.'