No full-time officer or employee of the Department of the Interior who directly or indirectly discharged duties or responsibilities under this subchapter, and who was at any time during the twelve months preceding the termination of his employment with the Department compensated under the Executive Schedule or compensated at or above the annual rate of basic pay for grade GS-16 of the General Schedule shall—

(1) within two years after his employment with the Department has ceased—

(A) knowingly act as agent or attorney for, or otherwise represent, any other person (except the United States) in any formal or informal appearance before;

(B) with the intent to influence, make any oral or written communication on behalf of any other person (except the United States) to; or

(C) knowingly aid or assist in representing any other person (except the United States) in any formal or informal appearance before,

any department, agency, or court of the United States, or any officer or employee thereof, in connection with any judicial or other proceeding, application, request for a ruling or other determination, regulation, order, lease, permit, rulemaking, or other particular matter involving a specific party or parties in which the United States is a party or has a direct and substantial interest which was actually pending under his official responsibility as an officer or employee within a period of one year prior to the termination of such responsibility or in which he participated personally and substantially as an officer or employee; or

(2) within one year after his employment with the Department has ceased—

(A) knowingly act as agent or attorney for, or otherwise represent, any other person (except the United States) in any formal or informal appearance before; or

(B) with the intent to influence, make any oral or written communication on behalf of any other person (except the United States) to,

the Department of the Interior, or any officer or employee thereof, in connection with any judicial, rulemaking, regulation, order, lease, permit, regulation, or other particular matter which is pending before the Department of the Interior or in which the Department has a direct and substantial interest.