Speaking at defence manufacturer PIT-Radwar in Kobyłka, near Warsaw, on Friday, Tusk said the programme was Poland's own initiative.
"We told Brussels what this project should look like – not the other way around," he said.
Parliament votes on amendments
The Sejm lower house of Polish parliament is set to vote on Friday on upper-house amendments to the law implementing SAFE.
The amendments seek to ensure loan repayments do not come from the defence ministry budget, and introduce oversight by Poland's security, anti-corruption and counter-intelligence agencies.
Polish industry to benefit
Tusk said more than 80 percent of SAFE funds would go to Polish firms and the Polish arms industry.
He stressed that German industry would benefit by just 0.37 percent – and only through a Swedish-German company.
"It is also a major injection of opportunities, money and technology into the Polish arms industry and all its contractors," he said.
US relations unaffected
The prime minister also sought to reassure allies, saying SAFE would not affect Polish spending on American equipment.
"We will be an even better ally thanks to SAFE," he said, describing the arrangement as a "win-win."
According to Tusk, around 12,000 Polish firms would be eligible to benefit from the funds.
A significant share of the funds would go towards advanced technologies including satellites, cyber defence and counter-drone systems, with a large portion dedicated to the Eastern Shield border fortification project.
(ał)
Source: PAP