Press TV- Secretary of State Mike Pompeo says the United States will not lift economic sanctions against North Korea until Pyongyang fully eliminates its nuclear weapons capability.

A complete, verifiable and irreversible denuclearization �is the only outcome that the United States will accept,� Pompeo told reporters on Monday in Singapore. �If diplomacy doesn�t move in the right direction, sanctions will increase.�

The stern warning came ahead of a historic summit between President Donald Trump and North Korean leader Kim Jong-un in Singapore on Tuesday.

Trump and Kim arrived in Singapore on Sunday to hold the first ever face-to-face meeting between leaders of the two countries, which have remained enemies since the 1950-1953 Korean War.

Officials from the two countries are holding discussions to narrow the differences and make the final preparations for the anticipated summit.

Pompeo said the negotiations are �moving quite rapidly and will come to a logical conclusion more quickly than anticipated.�

While the summit is seen as a test for diplomacy that could end the long-running nuclear standoff, foreign policy experts say the stakes are high if it does not result in a nuclear agreement.

Pompeo said Washington is prepared to offer �unique� security guarantees to Pyongyang if it embarks on a complete denuclearization.

In return, he said, "We will take actions to provide them sufficient certainty that they can be comfortable that denuclearization is not something that ends badly for them."

�I�m very optimistic that we will have a successful outcome from our meetings tomorrow,� the top diplomat said.

Experts say the talks could run into trouble because the US and North Korea hold different understandings of what it means for the latter to denuclearize.

Trump and Kim have yet to agree even on how to define denuclearization of the Korean Peninsula.

The US seeks the complete and irreversible dismantling of North Korea�s nuclear program. Pyongyang is demanding a solid guarantee of its security and the removal of Washington�s nuclear umbrella protecting allies South Korea and Japan.

The North has also sought an end to the US military presence in the South, where Washington has around 28,000 troops.

So far the US has failed to provide details on what kind of security guarantees it is prepared to offer.