President Obama stopped short Wednesday of firing Department of Veterans Affairs Secretary Eric Shinseki, expressing anger over delays in treatment that reportedly led to dozens of deaths at Veterans Affairs hospitals but reserving further action until an investigation is completed.

“I will not stand for it,” Obama said from the White House briefing room, addressing the firestorm publicly for the first time in more than three weeks.

“If these allegations prove to be true, it is dishonorable, it is disgraceful, and I will not tolerate it, period,” he added.

Obama met earlier Wednesday in the Oval Office with Shinseki and Deputy White House Chief of Staff Rob Nabors, who is leading the administration’s review of the VA allegations.

Obama called Shinseki a "great soldier" and expressed confidence in the VA leader to fix the situation.

Veterans groups, though, were frustrated that Obama didn't force him out.

"The question is this: If the administration has known about these issues for at least four years, why is it just now taking action?” said American Legion National Commander Daniel Dellinger.

“Moreover, the president’s decision to keep Secretary Shinseki at his post is an unfortunate one,” he added.

The White House has been on the defensive over allegations of backlogs in disability claims, phony waiting lists for medical care and deaths at VA hospitals nationwide.

Republicans have accused the president of being unresponsive to the issue, which they say is indicative of broader failures with his leadership style.

Obama accepted the resignation of the VA's top health official, Robert Petzel, last week, although he was already scheduled to retire in 2014. But Obama continues to stand behind Shinseki, a retired four-star general and former Amy chief of staff.

Nabors will travel to Phoenix on Wednesday to meet with the head of the VA health care system there. Allegations recently surfaced that 40 veterans died while waiting for care at the facility and that workers there concocted a secret waiting list and tried to destroy the evidence.

And new allegations are surfacing seemingly every day.

According to the VA’s inspector general, 26 facilities nationwide are under investigation for treatment delays and falsifying records.

Obama pledged Wednesday to get to the bottom of the barrage of issues at VA hospitals.

“We are going to fix whatever is wrong,” Obama said, speaking directly to veterans.

Republicans, however, were quick to dismiss the president's remarks.

“Why did President Obama wait to address this situation only to ask our veterans for more time and to offer nothing but words?" asked Republican National Committee Chairman Reince Priebus.

"We've known about these problems for weeks — facilities cooking their books, veterans dying while waiting for an appointment, and bonuses being handed out to those in charge," he added. "The administration, we now know, has known about them even longer."

And GOP lawmakers said Obama was failing in his duties as commander in chief.

“Every day that we have waited for President Obama and Secretary Shinseki to show leadership, new complaints and concerns poured in from whistleblowers, veterans and veteran family members across the country,” said Sen. Jerry Moran, R-Kansas, who serves on the Senate Veterans Affairs Committee. “There is a difference between wanting change and leading it to happen.”

This article was originally published at 11:23 a.m. and has since been updated.