Key Points:

Senior doctors have each been offered salary increases of 13.3 per cent over three years, and an immediate $10,000 lump sum payment as a "retention" bonus.

The bonanza settlement follows an unusual last-ditch intervention by Health Minister David Cunliffe in February after nearly two years of bitter pay negotiations between the Association for Salaried Medical Specialists (ASMS) and district health boards (DHBs).

The pay rise will also help the association's 2800 members by boosting the dollars in their availability allowances of about 7 per cent of their salaries, and will also ensure higher overtime payments of at least time-and-a- half, and doubling of allowances for continuing medical education to $16,000.

ASMS members are voting in a postal ballot on the deal, which will plug in a couple of new pay grades for senior specialists, whose base pay will go up to nearly $200,000.

The salary for top specialists will jump by $40,565 a year to $248,210, plus their $10,00 retention bonus, which is likely to be paid on May 8, when the union national executive will consider its members' voting on the proposed settlement.

In the middle of the 15-level pay scales, at step 9, the salary will lift $24,577 to $209,362, plus the $10,000 retention bonus, and lower down, at step 3, it will lift $20,522 to $174,827, plus the $10,000 payment.

The national executive said in a special bulletin to members that the term of the settlement to April 2010 is too long, and that it will not resolve the recruitment and retention crisis, but it is recommending members endorse it.

"We have exhausted our capacity to scratch out more by negotiation alone," the association said.

Instead, it has also won cabinet approval for an independent commission to investigate and make recommendations on "competitive and sustainable" terms of employment for senior medical staff working for DHBs.

This will include comparisons with similar jobs in Australia and in the private sector - without being constrained by Government or DHB funding limits - and will report to the Health Minister by March 31 next year, after the general election.

Meanwhile, additional benefits for doctors will include a guarantee of a minimum rate of double the specialists' step 9 pay scale when asked to cover unexpected absences by resident medical officers, wider entitlement to paid leave for meetings of professional associations, and a new requirement for DHBs to provide good quality overnight accommodation for senior medical officers who have to stay in the hospital at night.

The union has been negotiating with DHBs since May 2006, and about 1900 senior doctors voted late last year to strike. They were due to start walking off the job from next month, until Mr Cunliffe intervened in an "all-night" meeting on March 5 with union, DHB and Health Ministry representatives.

Meanwhile, members of another doctors' union, the New Zealand Resident Doctors Association (NZRDA) intend to strike for 48 hours starting on April 22.

DHBs have started planning for the strike, which would reduce hospitals to emergency services and delay non-urgent surgery and elective treatments.

Mr Cunliffe has said he will not rule out intervening in the junior doctors' dispute, but he does not believe that the normal discussion process has yet been exhausted.

Junior doctors are claiming three base-pay increases of 10 per cent a year plus increases in other allowances and rates that DHBs have claimed would push the costs to 40 per cent in total, or more than 13 per cent a year.