Former President George H.W. Bush backs John McCain's efforts to increase support for the Iraq war in a new video, a telecast that aides to both men say shouldn't be construed as an endorsement of McCain's White House bid.

On Monday night, the former president appeared in the video shown at South Carolina's military college, The Citadel, during the final stop of the Arizona senator's "No Surrender" tour.

"The bottom line is we must persevere; we must not surrender; we must not quit and run away. God bless our troops and everyone involved in the 'No Surrender' rally there in Charleston," Bush said, according to a transcript of the video provided by the McCain campaign.

Bush also praised McCain and South Carolina Sen. Lindsey Graham, who will work in the Senate on turning back Democratic efforts to limit U.S. troops' time in Iraq.

"I salute Senators McCain and Graham for their sponsorship and for standing tall," Bush said.

McCain traveled to the early voting states of Iowa, New Hampshire and South Carolina on "No Surrender" tour in which he stressed his strong support for the war and President Bush's increase of some 30,000 troops earlier this year.

Jean Becker, chief of staff for the former president, said the video was "intended to support the troops and not intended as an endorsement for Senator McCain." McCain's campaign hasn't misrepresented the video, she said.

Bush remains neutral in the 2008 race and, while he likes McCain, he's just as close to Mitt Romney, Rudy Giuliani and Fred Thompson, Becker said.

B.J. Boling, McCain's South Carolina spokesman, also said the video should not be seen as an endorsement.

"What you have is a former president who is incredibly patriotic and understands the enemy America faces and is saluting Senator McCain's efforts to convey to the American people that surrender is not an option," Boling said. "We're thrilled to have former President Bush supporting Senator McCain's efforts against radical Islam."

McCain has criticized President George W. Bush's handling of the war. On Saturday, he blamed the Bush administration for presenting rosy scenarios in Iraq that have frustrated Americans and said Bush failed to curb them.

"It's all the president's responsibility," he said.