GOP leaders in the House are pressing forward with implementation of a strict unilateral earmark ban despite the fact that their colleagues in the Senate appear to have no interest in playing along.

House Republican leaders sent GOP Members a guidance document Tuesday to explain the self-imposed earmark ban and warn the rank and file against trying to circumvent the new Conference rule.

Senate Republicans met on Wednesday to discuss the possibility of their own earmark moratorium, but the caucus remains deeply divided and the meeting generated no agreement on limiting earmarks.

The House GOP Conference approved the moratorium by voice vote last week after Democrats approved a narrower ban on earmarks to for-profit entities. But many House Republicans and their aides complained privately that in their rush to pass the ban, GOP leaders failed to take into account how it would affect huge authorizing bills such as those that deal with transportation and defense projects.

Tuesday’s four-page memo, obtained by Roll Call, reiterated that the moratorium affects all earmarks — including those that are tariff- and tax-related — as well as those made for defense, transportation and other authorizing bills.

“Members who submitted requests for the FY ’11 Appropriations process and/or the FY ’11 National Defense Authorization bill should work with the Committee contact [person] and withdraw those requests prior to the request deadline,” the memo said.

It also outlined how Members should go about withdrawing requests already made to the various authorizing committees and included a sample withdrawal letter.

“With respect to the Water Resources Development Act (WRDA) and Surface Transportation Reauthorization requests where the request period has closed, Members will personally withdraw their request via written letter to [Transportation and Infrastructure] Ranking Member [John] Mica (R-Fla.),” the memo said.

“While some items may fall into a ‘gray area’ the ultimate determination as to what is and what is not an earmark rests with the Committee Chairman of jurisdiction,” the memo said. “Therefore, if you are not certain whether a proposal meets the definition of an earmark included in House Rules, contact the Ranking Member’s office for the Committee of jurisdiction.”

Mica said in an interview that while Members would have to pull their requests for projects, it was unlikely that these bills would make it to the floor this year.

“There’s a possible problem, but it’s also unlikely that any of those bills will get done this year,” Mica said. “Until we have some reforms and protocol that my Conference feels are adequate to make the process more transparent and equitable, we are all on hold.”

Another Republican Member said that if a new highway bill is not taken up this year, Republican-sponsored projects that were included in the last bill would probably continue to be funded through any extension legislation passed by the House.

“All of those projects will stay in there,” the Member said.

Rep. Jack Kingston (R-Ga.), a member of the Appropriations Subcommittee on Defense, said that in many ways the earmark ban could end up costing the government more money than it saves.

As an example, Kingston pointed to the fact that many small defense contractors, who can receive work through Congressional earmarks, tend to charge less than their larger counterparts.

“As usual, we threw the baby out with the bath water,” Kingston said. “You can argue that what we have done doesn’t save money, it just complicates it.”

Kingston predicted that earmarks that would have been requested through the House would simply end up going through the Senate.

“The Senate is not impressed with this,” he said.

The leadership memo said that the only exceptions to the new rule would be made for Republican earmarks already included in bills that passed the House before the March 11 ban was implemented and that Members should “refrain” from adding any additional requests in any future conference reports that return to the House floor.

“While it is impossible for Members to individually rescind action taken by the whole House, consistent with the policy adopted by the Conference, House Republicans should refrain from requesting that any earmark be included in any bill being considered by the Senate or in any Conference Report,” it said. For earmarks that have already been approved, “Members associated with such earmarks should refrain from using official resources to promote their association with such earmarks.”

Several House Republicans said the ban was fairly unpopular within the Conference but passed because leadership announced support for the measure the night before last week’s Conference-wide vote.

At least one Republican, Rep. Don Young (Alaska), indicated he would not abide by the new GOP rule. Young told a local newspaper on Friday that he would continue to make requests if his constituents deemed them necessary.

The memo warned Members against trying to circumvent the rule and reminded them that any attempt to ask another Member of Congress to insert a request into a bill on their behalf could lead to an ethics violation.

“While the Committee on Standards of Official Conduct has never issued final guidance on what constitutes a ‘request,’ a draft circulated by the Ethics Committee in 2007 stated that ‘Asking another Member to request a measure on one’s behalf may also constitute a request’ under the Code of Conduct,” the memo said.

Senate Minority Leader Mitch McConnell (R-Ky.) called Wednesday’s special meeting of the Republican Conference in the wake of the House GOP’s earmark ban, hoping to allow his Members to air their views on the issue and float potential proposals for addressing the controversial practice.

“There were some thoughtful statements being made,” said Sen. Judd Gregg (R-N.H.), a member of the Appropriations Committee who opposes banning earmarks.

Sen. Jim DeMint (R-S.C.), who has spearheaded a push for Senate Republicans to join their House counterparts and unilaterally disarm on earmarks, left the meeting early, saying that “nothing was decided.”

DeMint also brushed off criticism from Sen. James Inhofe (R-Okla.), one of the fiercest defenders of the practice in the Senate. Earlier in the day Wednesday, Inhofe had taken to the Senate floor and ticked off a list of South Carolina highway projects for which DeMint had previously sought earmarks.

“I’m a recovering earmarker,” DeMint said when asked for reaction to Inhofe’s speech. “The first step to recovery is figuring out you have a problem. It’s time the rest of them do that.”

John Stanton contributed to this report.