US President Donald Trump’s reported plan to slash the number of American troops stationed in Germany has caused concerns that he may seek to take a similar step in South Korea.

A further prolonged deadlock in defense cost-sharing negotiations between Seoul and Washington could prompt Trump to threaten and actually attempt to scale down the 28,500-strong US Forces Korea.

The 2020 National Defense Authorization Act passed by the US Congress calls for, among other things, maintaining the number of American soldiers stationed in South Korea at the current level. But it permits the downsizing of USFK if the measure suits American national interests.

Media reports said Friday that Trump has ordered the Pentagon to cut the number of US military personnel assigned to Germany by 9,500 from the current 34,500.

There has not yet been any confirmation from US officials about the move. But in recent years Trump has been accusing Germany, which hosts more US troops than any other European country, of not spending enough on defense.

Some observers here say there are differences in the function and roles of US forces deployed in Germany and South Korea. The mission of American troops in Germany carries less strategic urgency than that of USFK tasked with coping with the mounting nuclear and missile threats from North Korea.

South Korea’s defense spending also accounts for more than 2 percent of its gross domestic product, meeting the demand the Trump administration has been making with Germany and other European members of the North Atlantic Treaty Organization. Berlin plans to gradually increase the proportion, which remained at 1.36 percent last year, to 2 percent by 2031.

Washington has also been irked by Berlin’s adherence to the Iranian nuclear deal and support for a Russian gas pipeline.

But it cannot be ruled out that Trump will move to downsize US forces deployed here if Seoul continues to refuse to accept what he sees as a fair cost-sharing deal. He might be more than ready to set aside the strategic importance military leaders attach to the upkeep of USFK and insist that saving the cost of helping defend an ally unwilling to shoulder its due burden would not harm US interests.

His alleged order to reduce the number of American troops in Germany can be seen as adding to pressure on Seoul to become more flexible on the defense cost-sharing deal.

South Korea and the US have failed to bridge their differences in the seven formal rounds of negotiations since September on how to revise the cost-sharing accord, known as the Special Measures Agreement.

South Korea rejected a proposal made by the US last month to raise its share of the cost for the USFK upkeep to $1.3 billion this year. Trump is said to have endorsed the offer.

Washington initially called for a fivefold increase in South Korea’s payment to around $5 billion.

Seoul has stuck to a position that its best offer is a 13 percent increase from its payment last year. Under the 2019 SMA, which expired in December, Seoul was required to pay $870 million, up 8.2 percent from the previous year.

Washington has urged Seoul to show more flexibility in response to its decision last week to accept the latter’s proposal to fund wages for Koreans working at US bases here. On April 1, USFK placed nearly half of its 8,600 Korean employees on unpaid leave for an indefinite time, citing the lack of a new SMA.

Now Seoul seems to be in need to depart from its focus on technical issues such as additional areas to be covered by the burden-sharing accord. It remains adamant on maintaining the framework of the deal, which limits its financial contribution to wages for local employees, the construction of military facilities and other logistics.

Whereas, Washington is said to be urging Seoul to pay for the cost of the rotational deployment of an infantry brigade from the US mainland to South Korea. Observers say Trump might consider suspending or gradually downsizing the rotational deployment if he decides to reduce the US military presence here.

South Korea needs to consider accepting the measured expansion of the scope covered by the SMA. It could match the concession with a demand that the cost-sharing deal be renewed on a multiple-year basis instead of being renegotiated annually.

The allies should no longer let the deadlocked negotiations strain their relations at a time when they need to strengthen cooperation in coping with growing signs of provocation from North Korea and preparing for the post-coronavirus pandemic era.