Republican presidential hopeful John McCain issued a statement Wednesday night saying he "will not allow a smear campaign" to distract from his campaign as published reports questioned his relationship with a lobbyist. The Washington Post quoted longtime aide John Weaver, who split with McCain last year, as saying he met with Vicki Iseman and urged her to stay away from McCain. The New York Times suggested an inappropriate relationship between the Arizona senator and Iseman, a Washington lobbyist. The New York Times quoted anonymous aides saying they had confronted McCain and Iseman, urging them to stay away from each other, before his failed presidential campaign in 2000. Eight years later, McCain is close to securing the GOP nomination. Aides said the senator would address the allegations at a news conference Thursday morning. The published reports said McCain and Iseman each denied having a romantic relationship, and the paper offered no evidence that they had, saying only that aides worried about the appearance of McCain having close ties to a lobbyist with business before the Senate Commerce Committee on which McCain served. The story alleges that McCain wrote letters and pushed legislation involving television station ownership that would have benefited Iseman's clients. In a statement issued by his presidential campaign, McCain spokeswoman Jill Hazelbaker said: "It is a shame that The New York Times has lowered its standards to engage in a hit-and-run smear campaign. "John McCain has a 24-year record of serving our country with honor and integrity. He has never violated the public trust, never done favors for special interests or lobbyists, and he will not allow a smear campaign to distract from the issues at stake in this election. "Americans are sick and tired of this kind of gutter politics, and there is nothing in this story to suggest that John McCain has ever violated the principles that have guided his career." McCain's campaign also issued a lengthy statement insisting that his actions did not benefit any one party or favor any particular interest. McCain defending his integrity last December, after he was questioned about reports that the Times was investigating allegations of legislative favoritism by the Arizona Republican and that his aides had been trying to dissuade the newspaper from publishing a story. "I've never done any favors for anybody - lobbyist or special-interest group. That's a clear, 24-year record," he told reporters in Detroit. McCain and four other senators were accused two decades ago of trying to influence banking regulators on behalf of Charles Keating, a savings and loan financier later convicted of securities fraud. The Senate Ethics Committee ultimately decided that McCain had used "poor judgment" but that his actions "were not improper" and warranted no penalty. McCain has said that episode helped spur his drive to change campaign finance laws in an attempt to reduce the influence of money in politics. In late 1999, McCain twice wrote letters to the Federal Communications Commission on behalf of Florida-based Paxson Communications - which had paid Iseman as its lobbyist - urging quick consideration of a proposal to buy a television station license in Pittsburgh. At the time, Paxson's chief executive, Lowell W. "Bud" Paxson, also was a major contributor to McCain's 2000 presidential campaign. McCain did not urge the FCC commissioners to approve the proposal, but he asked for speedy consideration of the deal, which was pending from two years earlier. In an unusual response, then-FCC Chairman William Kennard complained that McCain's request "comes at a sensitive time in the deliberative process" and "could have procedural and substantive impacts on the commission's deliberations and, thus, on the due process rights of the parties." McCain wrote the letters after he received more than $20,000 in contributions from Paxson executives and lobbyists. Paxson also lent McCain his company's jet at least four times during 1999 for campaign travel.