US President Donald Trump will not be traveling to Switzerland this month to attend the World Economic Forum in Davos, he announced via Twitter, as a confrontation regarding funding for a border wall drags on.

The impasse in talks with Democratic lawmakers has held up legislation needed to fund some federal government agencies, leaving around 800,000 workers without pay, some of whom are still required to work.

“I am respectfully cancelling my trip to Davos,” Trump wrote, citing the Democrats’ “intransigence.”

In terms of foreign policy, the cancellation puts an end to speculation that Trump will hold talks with Chinese Vice-President Wang Qishan, a figure close to Chinese President Xi Jinping.

It was reported last week that the two would sit down on the sidelines of the economic summit, prompting further optimism that the US and China were inching closer to a trade deal. It would mark the highest-level meeting between the two countries since Trump and Xi met at the beginning of December.

Three days of negotiations in Beijing between mid-level trade delegations concluded on Wednesday, with both sides indicating that the talks were productive, though providing few details.

Prior to Trump’s announcement, White House officials said that Treasury Secretary Steven Mnuchin would be attending the summit.

The partial government shutdown now underway is expected to break the record for the longest in American history, as the president seeks to assure supporters he is serious about his signature campaign promise of building a wall on the southern border with Mexico.

Trump told reporters on Thursday that he would “probably” declare a state of emergency to divert funding from federal agencies to fund the wall if Democrats do not agree to funding.

That controversial option could lead to court challenges, some lawmakers say, but could also give Trump a pathway to signing legislation to reopen federal government agencies now shuttered without giving in on his promise to build the wall.