The Republican chair of the Senate Judiciary Committee pumped the breaks on the confirmation of a top health official Tuesday, saying the Obama administration didn’t adequately investigate claims that Planned Parenthood sold fetal issue.

Sen. Chuck Grassley (R-IA) said he would block the confirmation of Mary Wakefield as Health and Human Services deputy secretary until the administration better detailed the scope of its investigation into Planned Parenthood, an HHS grant recipient.

Grassley said in the Congressional Record that after he wrote to HHS about “fetal tissue harvesting practices at Planned Parenthood,” the “response to the letters did not fully answer the questions raised and, furthermore, raised additional concerns.”

After an anti-abortion group published surreptitiously filmed videos that purported to show Planned Parenthood executives discussing the sale of fetal tissue, the women’s health provider became the target of five congressional investigations, along with probes in multiple states.

Planned Parenthood Executive Vice President Dawn Laguens slammed Grassley’s “latest round of obstruction” as “a new low” in a statement provided to TPM.

“Grassley’s actions are reckless, irresponsible and threaten the health and safety of millions,” Laguens said in the statement.

Grassley is among the leading Senate Republicans blocking a potential Supreme Court nominee from President Obama.