In a predraft blockbuster trade, the St. Louis Rams have agreed in principle to send the second overall pick in this year's draft to the Washington Redskins for three first-round draft picks and a second-round pick.

The trade, first reported by FoxSports.com, cannot be signed off on, turned in and processed until the new league year starts at 4 p.m. ET Tuesday, but it is expected to become official then.

"In order to execute each of our club's plans for free agency and the upcoming draft, we have agreed to a trade between our two teams for the 2nd pick in the 2012 draft. We will submit this trade to the NFL for approval," Redskins general manager Bruce Allen and Rams general manager Les Snead said in a combined statement Saturday morning.

Rams chief operating officer Kevin Demoff also confirmed the deal Saturday morning to The Associated Press.

In the deal, the Rams will receive the Redskins' No. 6 overall pick this year, as well as the Redskins' first-round picks in 2013 and 2014. The Rams also will receive Washington's second-round pick this year in return for the second overall pick that the Redskins now will use on whichever quarterback the Indianapolis Colts do not draft No. 1 overall.

"We understand it was a heavy price but when you bought your home you probably wanted to pay a little less too," Washington general manager Bruce Allen said Saturday. "But you like your home once you live in it."

The deal was agreed upon early Thursday afternoon, but the NFL Management Council prohibited any announcement, a league source told ESPN senior NFL analyst Chris Mortensen. The Rams now have the sixth, 33rd and 39th overall picks in next month's draft.

The Redskins are paying a hefty price to move into position to take Heisman Trophy winner Robert Griffin III. It shifts the Redskins up four places from sixth in the April draft, leapfrogging any other team that would have an interest in Griffin, the Baylor quarterback.

"Stock in Superman socks just sky rocketed...," Redskins receiver Anthony Armstrong tweeted, referring to the Superman socks Griffin wore at the Heisman ceremony in December.

The widespread expectation is that the Colts will take Stanford's Andrew Luck with their No. 1 pick.

The Cleveland Browns had stepped up their efforts to try to acquire the No. 2 pick in recent days, going so far as to offer at least three No. 1 picks to the Rams and possibly even a second-round pick, according to one source familiar with the deal. Cleveland sensed it was going to get the deal done, only to be informed that St. Louis planned to deal the coveted No. 2 pick to the Redskins.

Cleveland general manager Tom Heckert acknowledged to The Associated Press on Thursday he had talked to the Rams.

"The question is whether we have enough to see what Colt can do, and I think we do," Heckert said, referencing Browns quarterback Colt McCoy. "If we catch more balls and protect him better, can Colt be a lot better? Yes. That's our goal. We still think Colt can play in this league, and it's our job to help him out."

The bold move demonstrates how badly the Redskins are in need of a franchise quarterback after two decades of struggles. Coach Mike Shanahan already has whiffed on three in his two seasons in Washington, with Donovan McNabb, Rex Grossman and John Beck combining to produce an 11-21 record.

"It's been tough and I feel for our fans and in many times we haven't been successful and we're trying to get it right," Allen said, "and I think we had a big step to get it right."

The trade will not change the Redskins' plans in pursuing Peyton Manning. They still intend to talk with and try to sign him, even if they are considered a long shot, a team official said.

The Redskins' offense needs upgrades at receiver and along the offensive line, and Manning would have to face his brother Eli of the New York Giants twice a year in the NFC East.

The Rams were in the market to trade because they already have their franchise quarterback, 2010 No. 1 overall pick Sam Bradford.

By sacrificing four premium draft picks, Shanahan is reversing the plan he set in motion last year to stockpile picks to rebuild Washington's depleted roster. The Redskins, however, have plenty of space under the salary cap and can be aggressive in plugging their holes when free agency begins Tuesday.

Grossman and Beck combined to throw 24 interceptions last year, putting the Redskins just one behind league leaders Philadelphia and Buffalo on the way to a fourth consecutive last-place finish in the division. McNabb, acquired in a trade from the Eagles, was the starter for the first 13 games in 2010, when Washington went 6-10.

Shanahan has won only one playoff game since John Elway retired after capturing the second of back-to-back Super Bowls with the Denver Broncos in 1998, and he hasn't been to the playoffs in his last five seasons as a coach.

The Rams haven't made the playoffs since 2004 and are rebuilding under new coach Jeff Fisher and GM Snead. They were 2-14 last year, tied with Indianapolis for the NFL's worst record, and before the trade were set to pick either first or second for the fourth time in five years.

The Rams are committed to Bradford despite a drastic fall-off in production last season, one year after Bradford was the NFL Offensive Rookie of the Year in 2010. The offense was the league's puniest with or without Bradford, who threw just six touchdown passes and missed six games with a high left ankle sprain.

St. Louis has holes elsewhere at wide receiver and backup running back behind Steven Jackson, and there's uncertainty on the line with tackle Jason Smith's history of concussions. The defense threatened the franchise record for yards allowed and special teams were awful, and needs help at tackle, cornerback and outside linebacker.

The player most often mentioned as the team's pick if it stayed at No. 2, Oklahoma State wide receiver Justin Blackmon, would fill one of the greatest needs. Most mock drafts project that Blackmon will be gone by the sixth pick, but the Rams could leverage their newfound wealth of picks to get him.

Information from ESPN senior NFL analyst Chris Mortensen and The Associated Press was used in this report.