UPDATE 1-Biden warns of responses if North Korea escalates, but open to diplomacy

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WASHINGTON, March 25 (Reuters) - President Joe Biden said on Thursday the United States remained open to diplomacy with North Korea despite its missile tests this week, but warned there would be responses if North Korea escalates matters.

Biden told his first White House news conference the suspected ballistic missile tests by Pyongyang violated U.N. resolution 1718.

"We are consulting with our allies and partners, and there will be responses if they choose to escalate. We will respond accordingly," he said.

"I'm also prepared for some form of diplomacy, but it has to be conditioned upon the end result of denuclearization," he added, referring to the U.S. effort to persuade North Korea to give up its nuclear weapons.

Asked if he agreed that North Korea was the top foreign policy issue he faced, Biden replied: "Yes."

North Korea launched two suspected ballistic missiles into the sea near Japan on Thursday, underscoring steady progress in its weapons program and ramping up pressure on Biden's administration even as it reviews its North Korea policy.

They would be the first ballistic missile tests by North Korea in nearly a year and the first reported since Biden took office in January.

The launches came just days after North Korea fired several cruise missiles in an exercise that Biden had played down as "business as usual".

The Biden administration is in the final stages of its North Korea policy review, officials have said, and has been simultaneously signaling a hard line on human rights, denuclearization and sanctions, while making diplomatic overtures that administration officials say have been rebuffed by Pyongyang. (Reporting By Jarrett Renshaw, Heather Timmons; Writing by Arshad Mohammed; Editing by Chizu Nomiyama and Daniel Wallis)