'A lot of work to be done': Senator discusses tax reform after Trump hosts bipartisan dinner The president was a "gracious" host, according to one senator.

 -- Breaded veal, pie and tax reform were on the menu at the White House on Tuesday evening as a bipartisan group of senators, top economic advisers and President Donald Trump met in what was termed a "constructive" meeting.

The meeting touched on a number of topics, but its focus was on tax reform, where the president "strongly stressed" his interest in getting a pro-growth tax reform package done "as quickly as possible," according to attendee Pat Toomey, R-Pa.

"We had a great substantive conversation on policy and a great outreach to Democrats, who by the way, I should point out, the three Democrats who were invited were invited because they were the only three Democratic senators who did not sign the letter which effectively declares a lack of interest on working with Republicans on tax reform," Toomey said in a call with reporters following the dinner.

The three Democratic senators who attended were Joseph Manchin of West Virginia, Heidi Heitkamp of North Dakota, and Joe Donnelly of Indiana. The three are all up for re-election next year and hail from red states that Trump easily won last year.

The Democrats each released their own statements following the dinner, describing the conversation in pleasant terms while stressing the need for tax cuts that will help the middle class. More importantly, they stressed the need to see something in writing.

There is officially no tax plan, yet.

However, Toomey described their discussions as substantive and constructive, and said the Democrats did signal an openness to a "considerably" lower top tax rate on American businesses. Trump has said he'd like to cut the corporate tax rate to 15 percent from the current rate of 35 percent, but Treasury Secretary Steve Mnuchin said in a public appearance at CNBC's Delivering Alpha conference in New York on Tuesday he didn't know if the cut would be that much.

The White House called the meeting "highly productive," saying in an official readout that the president's "bipartisan outreach efforts" demonstrate his commitment to deliver tangible results for the American people. An official also stressed that the purpose of the meeting was less about coming to an agreement than about getting both sides in the room to start a conversation.

There was also broad interest on both sides in crafting a net tax cut for middle-class families, which Toomey said the president was "adamant" about including in a tax reform package.

The president was apparently in a very good mood, with Toomey saying Trump took him and Sen. Ron Johnson, R-Wis., on a tour of the White House and Lincoln Bedroom following the dinner.

Despite Trump asking for an expedient resolution to the bill, the timeframe is in question.

"A lot of work has been done," Toomey said. "A tremendous amount of work has been done in fleshing out the details. It's not all finalized obviously, a lot needs to be done."

Toomey said nothing has been drafted yet, but "we're hoping to pass a budget resolution in one or both houses of Congress."

"I'm hoping that in October we get a budget resolution out of a conference committee so that both the House and Senate have passed the final budget legislation," Toomey said.

He said a tax reform bill would be worked on simultaneously through committees sometime by late September.

"The goal is by Christmas to have a tax reform bill on the president's desk, and I still believe that that's doable," Toomey said.

The president plans to continue his bipartisan push on Wednesday, hosting another bipartisan meeting on tax reform at the White House with 13 members of Congress. The White House has also said the president may travel to up to 13 states in the coming weeks as he makes an aggressive sales pitch for his top legislative priority heading into the fall.

The president is also using Twitter to push for swift congressional action, calling it the "biggest tax cut & tax reform package" in U.S. history and making the case that the devastation caused by Hurricanes Harvey and Irma add urgency to the matter.

ABC News' Mark Osborne contributed to this report.