The call was made as Four Seasons Health Care and three unions - the GMB, Royal College of Nursing and Unison marked the first anniversary of a ground-breaking joint recognition deal.
Justin Bowden, GMB National Officer, said: "This agreement was ground-breaking in the care sector. One year on it is working well from both the company and unions' perspective."
But he added: "The economic squeeze has led to a real terms reduction in the fees that local authorities pay for care home places. This cannot continue and if the sector is to attract and retain high quality staff then the care provider companies must be able to reward the workforce fairly for the vital jobs that they do and be properly funded by government to do so."