Bernie Sanders could participate in a one-on-one, leftwing versus right debate with Ted Cruz during the presidential primary, without violating restrictive rules set by the Democratic and Republican national committees. The two senators would just have to face off at their workplace, the US Capitol.

The first debate of the extended primary election will see the top 10 Republican candidates in a field of 16 face off in Cleveland on 6 August, in an event hosted by Fox News. Both parties have made clear that if candidates appear in unsanctioned debates, they will be barred from any official debates.

But staffers for both the DNC and RNC confirmed that the restrictions on presidential debates do not apply to debates held on the floor of Congress.

Sean Spicer, the chief strategist for the RNC, told the Guardian: “Senate business would not be a violation.”

Sanders, a self-professed democratic socialist who represents Vermont as an independent but is running for the Democratic nomination, attracting large crowds and performing well in the polls, has long expressed a willingness to debate Republican rivals one on one.

In an interview with MSNBC in June he said he wanted to do so in order to expose what he called “an absolutely reactionary agenda”.

In the interview, Sanders emphasized how much he valued “the clash of ideas”, which he said led to “people becom[ing] more engaged in the political process”.

“I think it’s a good thing for progressives,” he said. “I think it’s a good thing for American democracy.”

Ted Cruz accuses Mitch McConnell of lying. Guardian

Cruz, a rightwing hardliner who is trailing in presidential polls, this week departed from normal Senate behavior by accusing from the floor of the chamber one of his party leaders, Mitch McConnell, of lying.

He has welcomed the possibility of a debate with Sanders. In Iowa last week, he told reporters: “I welcome as many debates as possible,” adding that he was “in for any discussion”.

Now the two presidential candidates have the possibility of making such a debate happen, albeit with the caveat that it would have to happen on the Senate floor, according to the rules of that chamber.