However, the 70-year-old Nastase will be able to attend any of the four tennis majors because they "lie outside the jurisdiction of the International Tennis Federation," the ITF said.
During the tie, Nastase, the Romanian team captain, made "racially insensitive" comments about Serena Williams' unborn child, the London-based organization said in an emailed statement on Friday.
He also made "abusive and threatening comments" to British No. 1 Jo Konta and a female British reporter who had reported his comments about Williams.
Nastase also swore at the umpire and "made advances of a sexual nature" to British team captain Anne Keothavong during a World Group II playoff clash in the Black Sea resort of Constanta.
The ITF internal adjudication panel has suspended the former world No. 1 from acting in an official capacity in all of its team competitions and tennis circuits until 31 December 2020. He will also be banned from attending such events until 2019 and fined $10,000.
"Chocolate with milk?"
On the first day of the tie, Nastase had wondered out loud what skin color Williams' unborn child would have after Romanian No. 1 Simona Halep was answering a reporter's question about the 23-time grand slam winner.
"Let's see what color it has," Romanian and British reporters had quoted Nastase as saying. "Chocolate with milk?"
Williams and her fiance, Reddit co-founder Alexis Ohanian, are expecting their first child this summer. Ohanian is white.
The outbursts angered Williams, who condemned Nastase's behavior towards her and her fellow tennis players a day after the tie via Instagram.
"It disappoints me to know we live in a society in which people like Ilie Nastase can make such racist comments towards myself and unborn child, and sexist comments against my peers," Williams wrote at the time.
Nastase had been thrown out of the tie after he reduced Wimbledon semifinalist Konta to tears following a foul-mouthed rant directed at her, the umpire and Keothavong on the second day of the three-day competition when the British team had complained of crowd noise during a match.
Nastase's defense team told the ITF panel the two-time grand slam winner "comes from a nation where racism is not 'as delicate an issue as it may be in other parts of the world.'"
They went on to say "there is also no prior evidence of Mr Nastase being racist," pointing to his friendships and partnerships with the late Arthur Ashe and former French Open winner Yannick Noah, "as evidence to the contrary."