T. Milton Street Sr. - Mayor Street's brother, in case you forgot - yesterday threatened to sue the city solicitor for accusing him of failing to pay nearly $400,000 in business taxes.

Milton Street - who was indicted in November over his alleged failure to report $2 million in taxable income, in case you forgot that, too - said it was "totally ridiculous" for the city solicitor to seek back taxes based on what federal prosecutors allege he was paid.

"You can't go into a court of law and collect money based on allegations," Street said.

Street, 67, said he sent a letter to Romulo L. Diaz Jr., the city solicitor, late yesterday afternoon threatening to sue him and the "Street administration."

"I demand that you retract your statement immediately, follow proper procedures and due process, and stop trying to influence an election for public office," Street wrote to Diaz.

Street, who is running for a City Council at-large seat, accused Diaz of making the back-taxes claim to score political points for a future run for judge.

"Stay the hell out of politics," Street said in an interview.

Diaz laughed when told of Street's accusation.

"I'm just interested in doing my job as city solicitor," Diaz said. He called it "a pretty straightforward story."

The city's Revenue Department performed an audit based on the indictment, Diaz said. The department determined that Street owed $392,573 in taxes.

Diaz said the department tried to contact Street without success and then referred the matter to the city's Law Department for collection.

The city will take Street to court to collect the money, Diaz said.

Federal prosecutors allege that Street did not pay taxes on $2 million he was paid in Philadelphia International Airport consulting fees. His trial has been set for October.

Contact staff writer Robert Moran at 215-854-5983 or bmoran@phillynews.com.