Washington (CNN) President Donald Trump appears poised to make good on his vow to release a transcript of his first phone call with the Ukrainian President after a month-and-a-half-long debate among aides over the wisdom of making another conversation public.

In a transcript of the call reviewed by CNN, Trump offers his congratulations to Zelensky for his recent election victory and invites him to visit the White House. The call doesn't contain the problematic mentions of the Bidens or the 2016 election that have drawn scrutiny in the impeachment probe.

On Thursday, the President showed a group of visiting Republican senators the document during lunch, according to Sen. Kevin Cramer, R-North Dakota, who said Trump referenced the call "a couple of times" during the meal before asking the senators if they wanted to see it.

Cramer described the transcript as "short" and consisting of about one page of "real text."

The document, which has been circulating in the White House, has been the subject of debate over the last month. Internal disputes, political maneuvering and diplomatic differences complicated its rollout , people familiar with the matter said

Trump first raised the prospect of releasing the log of an April phone call with Volodomyr Zelensky on September 25, insisting it would help reenforce his innocence in the then-nascent impeachment crisis. He said at the time that Vice President Mike Pence's phone conversations should also be made public.

Ever since, White House advisers have debated the wisdom of releasing additional conversations with Zelensky after a transcript of Trump's July phone call failed to quiet allegations he was pressuring Ukraine to investigate his political rivals.

Trump said last weekend he would probably release the transcript on Tuesday. Tuesday came and went, and he announced on Wednesday the transcript would be released Thursday.

On Thursday morning, a White House official said timing of the release was "up in the air."

A White House official said the release of the transcript of Trump's first call with the leader of Ukraine has cleared all of the necessary hurdles to be released -- and was just waiting for Trump to sign off.

"First transcript is ready to go and awaits the go-ahead of the President," the official said, though the timing of the release remains "fluid," the official cautioned.

Even though the additional phone calls are not seen as troubling inside the White House, some officials view releasing any additional information as risky. They believe Democrats will find a way to weaponize the transcripts, and are wary of providing any more fuel to the impeachment fire. And even some officials not aligned with Trump see a dangerous precedent in releasing transcripts of a president's conversations with foreign leaders.

But a separate camp inside the West Wing -- which, based on his public comments, includes Trump himself -- believes releasing the additional calls will deflate Democratic accusations his administration was applying pressure on Ukraine for political reasons.

"You can have it anytime you need it," Trump said in September of the additional call transcripts. "And also Mike Pence's conversations, which were, I think, one or two of them. They were perfect. They were all perfect."

After those comments, Trump and Pence's aides began an effort to vet the call transcripts and weigh the benefits of releasing them. Resentments over the release of the July call still linger among staffers, some of whom view the move as a fatal mistake as the impeachment inquiry was getting underway. The document's rollout has been viewed in some corners as a disaster, though Trump himself has dug in, insisting the call was perfect.

Pence said last month he had "no objection" to releasing the transcript of his phone call and that his office was discussing the matter with White House lawyers. There hasn't been an update since. A person familiar with the matter said Pence's phone call is "buttoned up" and "squeaky clean," but there remains hesitancy at releasing it since it could make Trump's July phone call look worse by comparison.

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Trump's aides have settled on a strategic approach to releasing the transcripts, according to a person familiar with the plans, hoping to counter-program the start of the impeachment hearings. By making public transcripts they don't believe implicate the President or Pence, officials hope to convey they have little to hide.

Officials have discussed releasing the Trump and Pence transcripts separately to space out whatever positive effect they may yield, the person said.

Still, consultations with the Ukrainian government over releasing new call transcripts have also proved difficult, a person familiar with the matter said. After the July phone call was released, Zelensky told reporters he believed only the American side would be made public -- not his own comments.

"I think such things, such conversations between heads of independent states, they shouldn't be published," he said.

In congressional testimony this week, Ambassador Bill Taylor told lawmakers the Ukrainians were "livid" with the release of the July phone call, even though Trump said at the time that Secretary of State Mike Pompeo had cleared it with his counterparts.

"The United States gave the Ukrainians virtually no notice of the release," Taylor said in his testimony.

In the days following Trump's first hint in September he was open to releasing the additional calls, White House lawyers resurfaced the transcripts of Trump's April 21 conversation, along with the transcript of Pence's September 18 call, to determine if there's anything damaging or worrying, the sources said.

What they've found is less volatile than Trump's July phone call, when he is shown asking for a "favor" from Zelensky: opening investigations into the 2016 election and Hunter Biden and Burisma, the Ukrainian natural gas company. He also disparaged the onetime US ambassador to Ukraine, Marie Yovanovitch, who he recalled in the spring. There is no evidence of wrongdoing by Biden in Ukraine.

By comparison, Trump's April phone call is shorter and more congratulatory in tone, according to a person familiar with its contents and CNN's review of the transcript. Coming in the immediate aftermath of Zelensky's victory in Ukrainian presidential elections, the phone call was meant to start a relationship between the two leaders.

Trump also encouraged Zelensky to continue going after corruption in Ukraine, but didn't specifically mention the Bidens or the 2016 elections, according to the person familiar.

In an official readout of the call, the White House said Trump "expressed his commitment to work together with President-elect Zelensky and the Ukrainian people to implement reforms that strengthen democracy, increase prosperity, and root out corruption."

The notable differences in tone between the two calls could raise questions among impeachment investigators as to what changed in the three-month span. It is over those months that Trump's personal attorney ramped up his efforts in Ukraine, including his successful bid to oust Yovanovitch.

In his closed testimony, Lt. Col. Alexander Vindman -- the National Security Council's top Ukraine expert -- described enthusiasm among the administration's Ukraine experts following the April call, a marked contrast to the July conversation, which unsettled Vindman and other officials, prompting complaints to White House lawyers.

"The April 21st call is notable in my mind because it was actually a very good caII. It was exactly what we had -- we were hoping for," Vindman said, according to a transcript released on his interview. "Everybody was happy, high-fiving from that call because we were moving in the right direction on Ukraine."