The U.S. Congress should scrap two controversial copyright enforcement bills and start over with attempts to target foreign websites accused of infringement and counterfeiting, more than 70 groups have said.

With widespread concerns about the Stop Online Piracy Act (SOPA) and the Protect IP Act (PIPA), Congress needs to "take a breath, step back, and approach the issues from a fresh perspective," the groups said in a letter to lawmakers, sent Monday.

Among the groups signing the letter were Amnesty International, the American Library Association, Consumers Union, Public Knowledge, Fight for the Future and Human Rights Watch. Many of the groups signing the letter have opposed SOPA and PIPA. The letter comes as the lead sponsor of PIPA has indicated he wants to move forward with copyright enforcement legislation.

About 14 million people participated in Jan. 18 online protests against the two bills, the letter said. The bills would have harmed free speech, innovation, cybersecurity and job creation, the letter said.

"The concerns are too fundamental and too numerous to be fully addressed through hasty revisions to these bills," the letter said. "Nor can they be addressed by closed-door negotiations among a small set of inside-the-beltway stakeholders."

The groups asked lawmakers to "determine the true extent" of online infringement. Several critics have cast doubt on studies and numbers cited by the Motion Picture Association of America and the U.S. Chamber of Commerce, two groups that supported SOPA and PIPA. Supporters of the bills have argued that U.S. officials and copyright holders need new tools to combat foreign piracy.

Representative Lamar Smith, a Texas Republican and lead sponsor of SOPA, has said he doesn't plan to move forward with the legislation. A spokeswoman for Smith, asked about the letter, referred to a Smith statement in January. "It is clear that we need to revisit the approach on how best to address the problem of foreign thieves," Smith said then.

Smith also said he "welcomes input from all organizations and individuals who have an honest difference of opinion about how to address this widespread problem."

But Senator Patrick Leahy, a Vermont Democrat and lead sponsor of PIPA, has indicated he wants to push forward with legislation. Leahy, in a speech five days after the online protests, said he has "remained flexible in terms of the legislative language" needed to combat online piracy.

However, Leahy also said he hopes that "after a brief delay" groups can work together on improvements to PIPA.

"This is the opportunity for those who want changes in the bill to come forward, join with us and work with us," he added. "This is the time to suggest improvements that will better achieve our goals."

Grant Gross covers technology and telecom policy in the U.S. government for The IDG News Service. Follow Grant on Twitter at GrantGross. Grant's e-mail address is grant_gross@idg.com.