During testimony before a congressional committee, General Motors' CEO Mary Barra will apologize to those affected by several high-profile recalls and say the automaker "will do the right thing."

Barra will make the remarks during an appearance before the House Committee on Energy and Commerce's subcommittee on oversight and investigations on April 1. Her remarks were posted on the GM media website Monday.

Barra will say the automaker has been "fully transparent" with the committee and automotive regulators, and has acted quickly to address safety issues on a wide range of vehicles including Chevrolet Express vans, Chevrolet Cruze compact sedans, Silverados, and other vehicles prevalent in government and commercial fleets.

Addressing the families and friends of people who were injured or killed in crashes, including the 12 deaths attributed to a faulty ignition switch that stopped airbags from deploying, Barra will say, "I am deeply sorry."

The automaker has set up a Website dedicated to the recalls with constantly updated information, Barra said. GM is communicating through social media, and has assigned additional personnel to call centers. GM has asked dealers to provide loaner vehicles free of charge for recall-related repairs.

"These measures are only the first in making things right and rebuilding trust with our customers," Barra said. "As I've reminded our employees, getting the cars repaired is only the first step. Giving customers the best support possible throughout this process is how we will be judged."

Read Barra's full remarks here.