Theresa May said recommendations about pay levels for public servants including teachers and police officers would be considered "very carefully" but stressed the need to "live within our means".
The Prime Minister has been under pressure to end the 1% cap on public sector pay rises, with members of her Cabinet hinting the squeeze on incomes could be ended.
At Prime Minister's Questions Mrs May insisted she valued public sector workers and the services they provide but "I know we have to pay for them".
The Fire Brigades Union (FBU) said an offer from employers worth 2% on basic pay this year and a potential 3% from April 2018 showed the pay cap was "dead in the water".
But Mrs May said that was a separate issue, determined by their local authority employers rather than central government.
The Prime Minister said: "We have had three pay review bodies in the public sector reporting in March that covered doctors and dentists, NHS staff including nurses, and the Armed Forces and the Government accepted the recommendations in all three of those cases.
"The firefighters' award is not a matter that is determined by Government, it is determined by the employers and it is not subject to a pay review body.
"There are outstanding pay review body reports, those cover teachers, prison officers, police officers and senior salaries and the Government will consider those reports very carefully and will respond to them.
"But while we do that we will always recognise that we need to take those decisions against the need to live within our means."
Responding to Labour leader Jeremy Corbyn, Mrs May said they "both value public sector workers and our public services, but I know we have to pay for them".
Mr Corbyn accused the Prime Minister of "recklessly exploiting the goodwill of public servants", adding: "They need a pay rise."
But Mrs May said: "Our policy on public sector pay has always recognised that we need to be fair to public sector workers, to protect jobs in the public sector and to be fair to those who pay for it.
"That is the balance that we need to strike and we continue to assess that balance."
Mrs May and Chancellor Philip Hammond are facing pressure from a string of Government ministers to ease the 1% cap on pay rises.
Foreign Secretary Boris Johnson wants a wage boost for public sector workers and believes that the recommendations of independent pay review bodies which back increases should be followed.
Environment Secretary Michael Gove has insisted the Government must "listen" to the pay review bodies, while Defence Secretary Sir Michael Fallon said pay rates were "obviously something we have to consider not just for the army but right across the public sector as a whole".
Health Secretary Jeremy Hunt has said he has "a great deal of sympathy" for nurses' demands for higher rises.
Transport Secretary Chris Grayling acknowledged there were splits around the Cabinet table about the approach to the pay cap.
The Transport Secretary told BBC Radio 4's Today programme: "There is always going to be a debate around the Cabinet table about what to do and we are not all clones."
British Medical Association council chair Dr Chaand Nagpaul said: "There is clearly growing support for doctors, nurses and allied health professionals' message to the Government: that the pay cap is unfair, unacceptable and must be lifted.
"Doctors' pay has sharply declined, falling by 22% since 2005. Staff morale across the health service has been worsened by year-on-year real-term cuts to pay through the Government's public sector pay cap.
"The NHS is struggling to attract and retain doctors. A recent BMA survey has found that two-thirds of hospital doctors, and almost half of GPs, report vacancies in their departments and practices.
"With the NHS at breaking point, politicians cannot continue to duck this issue. Investing in the NHS workforce and providing fair terms and conditions must be a priority for this Government, otherwise the NHS simply won't be able to attract and keep the front-line staff needed to deliver safe, high-quality patient care."