Minnesota Sen. Al Franken said Tuesday he would oppose Minnesota Supreme Court Justice David Stras' nomination to the 8th Circuit Court of Appeals.

President Trump picked Stras, whom Trump formerly included on his short-lists for the Supreme Court vacancy filled by Justice Neil Gorsuch, to take a seat on the Midwestern federal appeals court.

"The president should be seeking out judges who bridge the issues that divide us," Franken said in a statement on Tuesday. "I fear that Justice Stras's views and philosophy would lead him to reinforce those divisions and steer the already conservative Eighth Circuit even further to the right."

Franken continued, "[R]ather than work together to select a nominee who is a judicial moderate, the White House had already settled on Justice Stras before first approaching me, and the president nominated him despite the concerns that I expressed."

Franken said he would not return a "blue slip" to the Senate Judiciary Committee on Stras' nomination. Under the Judiciary Committee's blue slip procedure, a state's senators are consulted by the governing administration before a president nominates a judge from that state, no matter the party affiliation, according to a Congressional Research Service report that explains the blue slip policy.

A senator can block a nominee whom he or she opposes from receiving a Senate Judiciary Committee hearing or vote.

By failing to return his blue slip, Franken is putting pressure on Minnesota's other senator, Amy Klobuchar, to do likewise and stand united against Stras.

Some conservative legal scholars have clamored for Senate Judiciary Committee chairman Chuck Grassley to scrap the blue slip practice in order to bypass Democratic obstruction of Trump's judicial nominees. It remains to be seen how Grassley will proceed.