Inspired by Hillary Clinton’s crushing defeat in three Democratic presidential primary contests in Washington, Alaska, and Hawaii over the weekend, Bernie Sanders called for a televised debate with the former Secretary of State sometime prior to the significant primary in New York on April 19.

The last head-to-head debate between the two Democratic Party rivals took place on March 9 in Miami, Florida, and it's about time for a new face-off to give potential voters food for thought, the Vermont senator believes.

"I would hope very much that as we go into New York state, Secretary Clinton's home state, that we will have a debate…on the important issues facing New York and, in fact, the country," Sanders said Sunday on NBC's Meet The Press.

Clinton, however, rejected the call for debate. Her excuse? The "tone" of Sanders' campaign.

"This is a man who said he'd never run a negative ad ever. He's now running them. They're planning to run more," Clinton operative Joel Benenson said Monday. "Let's see the tone of the campaign he wants to run before we get to any other questions."

Benenson denied that there's any risk to the Democratic front-runner, saying that it's just not for Sanders to decide on the schedule.

"She's done very well in the debates…but Sen. Sanders doesn't get to decide when we debate, particularly when he's running a very negative campaign against us," Benenson said, adding that it is not a final "no" and that the answer will depend on the "kind of tone" the senator sets.

In a letter to Clinton's campaign manager Robby Mook, his counterpart in the Sanders campaign, Jeff Weaver, accused Clinton of "seeking some tactical advantage," noting that the two campaigns had previously agreed to "three additional debates — one in March, one in April, one in May in return for our campaign agreeing to the late scheduled debate in New Hampshire prior to that state's primary."

There are 247 delegates at stake in the April 19 primary in New York.

Since Sanders won in all three Democratic presidential contests on Saturday, he has raised more than $4 million, which will most likely be spent on advertising in upcoming states such as Wisconsin, New York and Pennsylvania.