South Korean President Lee Jae Myung has renewed efforts to regain wartime control of the country’s military from the United States and called for faster development of nuclear-powered submarines.

His push comes after President Donald Trump ordered the Pentagon to substantially reduce joint US-South Korean military exercises, saying North Korea had been respectful and that he had a good relationship with Kim Jong-un.

Lee said South Korea should continue preparing to take control of its forces during wartime, arguing that stronger independent capabilities would also strengthen the US-South Korea alliance.

The scaled-back Ulchi Freedom Shield exercises were intended to help certify South Korea’s readiness for the transfer, while US and South Korean officials have warned that North Korea’s military has gained new battlefield experience from supporting Russia in Ukraine, The Guardian has reported.

Despite the changes, Seoul said the exercises are defensive and intended to protect the Korean people rather than provoke North Korea or increase tensions on the peninsula.