Lawmakers in the US House of Representatives have voted to bar Chinese defence firms from receiving Pentagon contracts.
The amendment was passed as part of a larger defence budget bill passed by the House in Washington on Wednesday.
It excludes all companies owned by or affiliated to the Chinese government from US defence deals.
The US Senate must also pass the bill before it can be approved by President Barack Obama.
Congresswoman Rose DeLauro, a sponsor of the amendment, said it would help guard US national security interests.
"With China making significant progress in the defence and aerospace industries, including a Chinese state-controlled company considering a bid for the contract for the next presidential helicopter, it is critical that we ensure US national security is protected and that the highly skilled jobs and associated technologies in these industries are not outsourced overseas," she said in a statement.
"This amendment will help guard American interests, not only for our national security, but also the innovation, job creation and long-term economic growth."
Media reports, including one from the Wall Street Journal, say Chinese state-owned military contractor China Aviation Industry Corp (AVIC) may be making a bid for a contract to supply the US presidential helicopter.
Last week, a top Chinese general, Chen Bingde, said in Washington that China had no intention of matching US military power.
