LOS ANGELES (CBSLA.com) — Hundreds of registered nurses began a one-week strike Tuesday to push for their first contract with a medical union in Los Angeles.

At 7 a.m., nurses picketed outside of Kaiser Permanente Los Angeles Medical Center. A rally will also be held at 12:30 p.m. in the 4800 block of Sunset Boulevard.

According to the California Nurses Association (CNA) union, the walkout will affect 1,200 registered nurses who voted in July 2015 to join the union.

Union officials are pushing for upgraded patient-care staffing and improved economic benefits to attract new nurses while retaining experienced ones.

According to CNA, Kaiser has frozen wages for nurses at the hospital. Union officials want Kaiser to provide a contract with "strong patient care provisions," similar to those in other union contracts with the medical group.

In response to the walk-out, Kaiser says the tactic is "a disappointing attempt to disrupt patient care in the midst of contract talks."

Plans are in place to ensure that patient care is not affected, hospital officials said.

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