Embarrassed over a Colombia sex scandal, the US Secret Service has adopted new conduct guidelines that forbid agents from visiting "non-reputable establishments" or bringing foreigners to their hotel rooms.
The "enhanced standards of conduct," which are effective immediately, also forbid agents in the presidential protection force from consuming alcohol within 10 hours of reporting for duty, and require trips to be staffed by a supervisor from the agency's Office of Professional Responsibility.
The new behaviour policies will apply to Secret Service agents even when they are off duty while on official foreign trips.
The embattled Secret Service director, Mark Sullivan, urged agents and other employees to "consider your conduct through the lens of the past several weeks."
The Secret Service said it would conduct a training session on ethics, which will start next week.
The agency-wide changes were intended to staunch the embarrassing disclosures since April 13, when a prostitution scandal erupted in Colombia involving 12 Secret Service agents, officers and supervisors and 12 more enlisted military personnel who were there ahead of President Barack Obama's visit to a South American summit.
The new rules did not mention prostitutes or strip clubs, but they do stop employees from allowing foreigners, except hotel staff or foreign law enforcement colleagues into their hotel rooms.
They also ban visits to "non-reputable" establishments, which were not defined.
The State Department will be briefing Secret Service employees on trips about areas and businesses considered off-limits to them.
During trips in which the presidential limousine and other bulletproof vehicles are transported by plane, senior-level chaperones will accompany agents and enforce conduct rules, including one from the agency's Office of Professional Responsibility.
The Republican chairman of the House Homeland Security Committee, Representative Peter King, praised the new rules as "very positive steps by the Secret Service to make clear what is expected of every agent and also makes clear what will not be tolerated."
The Secret Service already has forced eight employees from their jobs and was seeking to revoke the security clearance of another employee, which would effectively force him to resign.
Janet Napolitano, the US homeland security secretary, assured Senators earlier this week that the incident in Colombia appeared to be an isolated case, saying she would be surprised if it represented a broader cultural problem.
However on Thursday a new report suggested that Secret Service staff had sex with strippers at a club in the Salvadoran capital, San Salvador, and took prostitutes into their hotel rooms last spring.
Sullivan said he was looking into the report but has so far not found anything "credible" to back it up.
The White House said on Friday that the president remained supportive of Sullivan and confident in the capabilities of the Secret Service.