A Senate panel set aside $100 million Thursday to develop a US rocket engine as an alternative to Russian equipment currently used to launch military satellites into orbit.
Amid broader disputes with President Vladimir Putin over Kremlin aggression in neighboring Ukraine, US lawmakers have considered ways to break from Russian rocket dependence, including blocking US firms from purchasing Russian-made engines and developing a new American-made engine.
"Mr Putin's Russia is giving us some problems," said Senator Bill Nelson, who flew aboard Space Shuttle Columbia in 1986.
"So we put $100 million in the defense bill to develop a state-of-the-art rocket engine to make sure that we have assured access to space for our astronauts as well as our military space payloads."
The bill was easily approved by the Armed Services Committee and now goes to a vote in the full Senate.
The House of Representatives passed its own defense bill, which also contains provisions aimed at reducing dependence on Russian delivery systems.
The two bills would need to be reconciled before becoming law.
The Pentagon currently depends on Russian-made RD-180 rocket engines to carry satellites into orbit. But US-Russia tensions threaten to spill into the space realm, where peaceful cooperation has ruled for decades.
Last month, amid high tensions over ex-Soviet Ukraine, Russian Deputy Prime Minister Dmitry Rogozin lashed out at US sanctions aimed at high-tech exports to Russia, warning that the move could endanger American astronauts at the International Space Station.
Rogozin signaled Moscow could prohibit the US from using RD-180s to launch Pentagon satellites, a move experts said could ground the US Defense Department Atlas V rocket for two to three years.
The Senate plan envisions a new US engine built within five years, Nelson said.
The world's astronauts have relied on Russian rockets for transport to the orbiting outpost ever since the retirement of the US space shuttle in 2011.
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