Ted Cruz, Ben Carson meet amid strained relationship

Charleston, S.C. — After two weeks of accusations and apologies, Ted Cruz and Ben Carson secretly met one-on-one on Thursday night in Greenville, South Carolina to discuss the pair's strained relationship.

But in a meeting that could have potentially settled Carson's continued frustration, the nearly half-hour meeting ended with little progress, according to an adviser with the Carson campaign.

"They agreed to disagree on the facts of what happened in Iowa," said Ryan Rhodes, an adviser to Carson who was outside of the meeting.

See images of Ben Carson on the campaign trail:

The Cruz campaign would only confirm that a "visit" took place in a tiny office near the stage in Greenville, where the pair was about to speak at the Conservative Review Forum on Thursday night.

The Daily Beast was the first to report about the meeting between the two candidates. Carson's Secret Service detail stood outside the locked doors as the candidates met.

Carson Adviser Ryan Rhodes told NBC News that the conversation "was intended to be a short, completely off-the-record meeting."

But the Carson campaign eventually knocked on the door because the conversation began to cut into Carson's speaking time at the forum.

The Carson campaign - intending for the meeting to be private - expressed its disgruntlement with the meeting becoming public.

"No one knew anything about this meeting except our two campaigns," Rhodes said.

See images of Ted Cruz on the campaign trail:

The meeting took place amid much criticism toward Cruz after his campaign pushed out information on the night of Iowa caucuses that Carson was leaving the state early and some suggested he was dropping out of the race.

Cruz's national co-chair Steve King, congressman from Iowa, tweeted that night: "Carson looks like he is out. Iowans need to know before they vote. Most will go to Cruz, I hope. "

The Carson campaign has blasted the Cruz campaign since then for its actions that night and its impact on Carson's candidacy.

Cruz issued a statement after the event, writing, "This was a mistake from our end, and for that I apologize to Dr. Carson."

But the apology did not satisfy the former pediatric neurosurgeon.

The pair's meeting on Thursday night seemed to do little to settle the matter.

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