Senate Democratic Leader Chuck Schumer and seven other senior Democratic senators have urged President Donald Trump to seek an interim deal with North Korea to support sustainable nuclear negotiations with the regime.

In a letter to the president dated Wednesday posted on the Senate Foreign Relations Committee website, the senators expressed growing concern that Trump's efforts to advance the goals outlined at the Singapore summit appear to be stalled and on the brink of failure. 

The letter points specifically to the goals of securing a "lasting and stable peace regime on the Korean Peninsula" and the "complete denuclearization of the peninsula" as examples.

The senators said the Trump administration has yet to develop a workable diplomatic process to structure real, serious and sustainable negotiations with North Korea.

They urged the administration to execute a serious diplomatic plan before it's too late, including a "sequenced process to verifiably freeze and roll back North Korea's nuclear weapons and missile programs in conjunction with continued appropriate sanctions and other pressure." 

The senators also called for a robust deterrence posture, strengthened alliances, intensified diplomatic engagement and a deepening of inter-Korean dialogue that can "provide a pathway to full denuclearization and a durable peace agreement."

They said that this should include a "phased process to verifiably dismantle the Yongbyon nuclear complex and other nuclear facilities."

The senators added that while such an interim agreement would only be a first step in a longer process, it would nonetheless be an important effort to create a real and durable diplomatic process that is necessary to achieve the complete denuclearization of North Korea.

The senators also warned that it would be a severe miscalculation to believe that a resumption of "fire and fury" threats against North Korea, which can increase the risk of a catastrophic war, can lead to better results than the negotiating table.