Most of North Korea’s naval drills involving submarines in the past seven years took place in 2018, when the two Koreas held talks three times to defuse tensions, Rep. Han Ki-ho of the opposition People Power Party said Tuesday, citing the Joint Chiefs of Staff.

The military found that the North deployed its submarines to rehearse attacks on the South about 150 times in 2018, the highest number since 2014, when such drills took place about 120 times. Excluding 2018 from 2015 to 2019, Pyongyang held the drill 87 times a year on average.

No drills took place in 2020 because of the pandemic, according to the military.

But the 2018 drills were not made public at the time, and since 2018, South Korea has cut back on its own naval drills with the US to counter North Korean submarines.

The Navy held submarine drills with the US only eight times, spending two weeks in total running them in 2018, while in 2016, the allies spent a little over a month holding them.

“This is catastrophic. North Korea still has eyes set on infiltration no matter what Moon says,” Rep. Han, a former three-star Army general, said, referring to President Moon’s push to sign a formal declaration with the North to end the 1950-53 Korean War, for which fighting stopped with only a cease-fire.

Inking the declaration is the cornerstone of Moon’s North Korea policy, which he describes as the first step before engaging the North in talks to dismantle its nuclear arsenal. The talks, which were last held in 2019, have since been in limbo because North Korea is refusing dialogue.

Speculation over a thaw in inter-Korean ties is mounting over hotlines the two neighbors reconnected Monday. Pyongyang had not responded to Seoul’s routine calls since August, accusing the South and the US of ramping up tensions with their annual military drills.

But North Korea has not withdrawn its conditions to reopen nuclear negotiations.

Pyongyang insists Seoul and Washington drop “double standards,” essentially demanding the two see its weapons tests as part of its self-defense and not a provocation, as the two allies consider their tests that way.

The North, which conducted a series of weapons tests in September in violation of UN sanctions, also demands the South and US scrap a “hostile policy,” which involves maintaining sanctions the UN and US imposed to halt the North’s nuclear and missile programs.

A senior official at the Unification Ministry, which handles inter-Korean affairs, said, “They are more like issues we have to work out together and not necessarily preconditions.”