If Russia wants to prove the country is a good trade partner, then the country must be more aggressive in fighting online piracy. That's the message a group of U.S. senators wants Vice President Joe Biden to send during his visit to Moscow this week.

A screenshot of file footage of U.S. Vice President Joe Biden.

In a letter written Friday by Senators Orrin Hatch (R-Utah), Bob Goodlatte (R-Va.), Adam Schiff (D-Calif.) and Sheldon Whitehouse (D-RI), the group reminded Biden that Russia appears to have once again grown soft on copyright violations and the lawmakers want him to nudge leaders there back on track.

For more than a decade, Russia has done too little to protect U.S. intellectual property, says the office of the U.S. Trade Representative and has earned a spot on a list of countries with poor records on enforcing copyright and intellectual property laws. Just last week, the USTR issued a report on "Notorious Pirate Markets" and accused several Russia-based sites of profiting from intellectual property theft.

Biden landed in Russia today for talks on multiple issues, including attempts by both countries to reduce nuclear arms and the turmoil in the Middle East. According to Reuters, Biden will meet with Russian President Dmitry Medvedev on Wednesday and Prime Minister Vladimir Putin on Thursday.

The trade groups for the U.S. film and music industries are among the copyright owners who want the U.S. government to close down U.S.-based sites that distribute pirated materials as well as cut off access in this country to overseas pirate sites.

For a while, Russia appeared to be cracking down. In 2007, Russia's government shut down Internationally-known Allofmp3.com, a music site accused of selling unauthorized music and later tried to toss the site's founder into jail . But as soon as Allofmp3.com went down a half dozen similar sites went online. The senators noted in their letter that more recently, Russia's communications and press minister said publicly that pirate sites should "be relieved of certain obligations to address piracy problems so long as they agree to take down infringing materials when notified."

In their letter, the senators, who are part of the Congressional International Antipiracy Caucus, suggested that Biden should use the World Trade Organization as leverage. Russia has been trying to win acceptance into the WTO for years.

"Addressing these rogue sites will go a long way toward demonstrating Russia's willingness and ability to operate under the rule of law," the senators wrote, "and therefore its preparedness to take on the obligations of membership in the [WTO]."

Biden is a big supporter of tougher copyright protection. Last year he angered many file sharers by declaring online piracy was no different than theft.