Tension between Arizona's two senators flared before the Senate ethics committee yesterday as an aide to Sen. John McCain (R) claimed that Sen. Dennis DeConcini (D) coaxed McCain into meeting with federal regulators on behalf of savings and loan executive Charles H. Keating Jr. to make the effort to help Keating appear bipartisan.

DeConcini's lawyer replied that the allegation was "pure speculation" and repeatedly raised questions about "leaks" of negative stories about DeConcini, suggesting that they came from McCain's office.

There was even a clash over whether Keating called DeConcini as well as McCain a "wimp" for refusing to go along with his requests. Aides to both senators appeared eager to claim the "wimp" characterization for their boss, almost as a badge of honor.

The exchanges came as the committee completed its examination of the first two witnesses, both McCain aides, during the fourth day of hearings on the propriety of five senators's intervention with federal savings and loan regulators on behalf of Keating, who had contributed $1.3 million to their campaigns and other political causes.

During the first three days, the senators, who also include Alan Cranston (D-Calif.), John Glenn (D-Ohio) and Donald W. Riegle Jr. (D-Mich.), told the panel they had broken no rules and done nothing wrong in connection with Keating and his failed Lincoln Savings and Loan Association of Irvine, Calif. Lincoln's collapse is expected to cost taxpayers at least $2 billion.

The first witness to be called before the committee, Gwendolyn Van Paasschen, who handled banking issues for McCain, said she believes DeConcini tried to get McCain to meet with federal thrift regulators in early 1987 "because Senator McCain was a Republican, and that would ensure that it was a bipartisan effort."

Keating had raised more money for McCain than he had for DeConcini, and so "if the press were to ever get a hold of it {news of the meeting}, it would be more embarrassing for Senator McCain than for Senator DeConcini," she said.

She said that in mid-March 1987 DeConcini tried to get McCain to go to the office of Edwin J. Gray, then chairman of the Federal Home Loan Bank Board, or to California to meet with San Francisco regulators to press for more favorable treatment for Lincoln.

"It was my view and I told Senator McCain . . . that it was my view that what Senator DeConcini had suggested was inappropriate," Van Paasschen said. McCain did not go, but attended two meetings shortly afterward on Capitol Hill in which the five senators discussed the case with Gray and other regulators.

James Hamilton, DeConcini's attorney, pressed Van Paasschen for evidence to support her theory, which he suggested was little more than speculation.

"His {DeConcini's} demeanor was very persuasive," she said. "He was coming to Senator McCain instead of Mr. Keating himself. He was a Democrat. We were Republican. And, as I said before, Keating had raised more for Senator McCain than he had for Senator DeConcini at that time."

McCain later distanced himself from Van Paasschen's allegations, saying he was not joining in making the charges. "She is a loyal staff member and entitled to her own views," he said.

McCain's rejection of DeConcini's proposal led to a charge by Keating that McCain was a "wimp." Keating's charge infuriated McCain, who gave Keating an angry "dressing down" when the two met in McCain's office a few days later, according to testimony yesterday by Christopher Koch, McCain's administrative assistant.

McCain told Keating he "had not spent 5 1/2 years in a {North Vietnamese} prisoner of war camp to have his courage or integrity questioned" in such a manner, Koch said.

Later, Hamilton asked Koch about a deposition taken earlier from DeConcini's chief aide, Gene Karp, in which Karp claimed Koch had told him that Keating also called DeConcini a wimp during his meeting with McCain.

"I don't recall it because it never happened," said Koch. Koch said he talked with Karp before the McCain-Keating meeting, so he could not possibly have made such a comment.

But Keating called McCain a "wimp" a second time in conversations with other senators in the Capitol, Koch said, further enraging McCain.

Meanwhile, Hamilton pressed both Van Paasschen and Koch about leaks to newspapers of evidence in the case that appeared damaging to DeConcini, suggesting strongly that they came from McCain's office.

One involved a DeConcini staff memorandum that listed bargaining positions that Keating wanted senators to present to federal regulators. Another concerned a letter from Bradley Boland, Keating's son-in-law, thanking DeConcini for "all that you have done" for Keating and his company and adding that he could not say the same for McCain, "who is probably the biggest disappointment in my life."

Both Van Paasschen and Koch denied leaking any of the documents, and Koch said he made inquiries of other McCain aides and was confident that they had not leaked them to the press.

Staff writer John E. Yang contributed to this report.