Presumptive Democratic nominee Hillary Clinton could not name one issue Wednesday that Sen. Bernie Sanders (I., Vt.) has caused her to change her position on or to embrace during the presidential primary.

Speaking with NBC News anchor Lester Holt, Clinton complimented Sanders for the energy he has brought to the Democratic Party this campaign season but refused to say that the Vermont Senator changed her views in any single policy area.

Clinton told Holt that she spoke with Sanders on Tuesday night after winning the California and New Jersey primaries “to really congratulate him on the extraordinary campaign he’s run.”

“I really appreciate all that he’s contributed to the Democratic Party and our country and the issues that we’re going to be focusing on in the general election. And I really look forward to working with him to unify our party,” Clinton added.

Clinton virtually locked up the Democratic nomination with her primary wins on Tuesday, which gave her an insurmountable lead in pledged delegates to add to her big lead with superdelegates, prominent party members who do not formally vote for a candidate until the Democratic convention this summer in Philadelphia.

Holt then asked Clinton, ”Can you name one idea that he’s [Sanders has] put forward that you want to embrace, that he has really changed your position on?”