Lt. Gov. Dan Patrick missed the first day of the Texas Legislature on Tuesday to attend a border security meeting at the White House.

Patrick, who attended a pre-session social event Monday evening in Austin and is scheduled for two public addresses on Wednesday, “is not going to be able to join us today,” said state Sen. Jane Nelson, a Flower Mound Republican, who took the dais in Patrick’s stead.

“He was called by the White House to discuss some issues that are critical to Texas,” Nelson told a Senate chamber full of lawmakers and their families. The leader of the upper chamber was sorry to miss swearing-in day, she said, but “when the White House calls you to Washington, you go.”

Patrick’s office said he was “called by the White House for an important meeting in Washington today on border security issues.” The meeting comes as the federal government enters day 18 of a partial shutdown that has come as the result of a stalemate between President Donald Trump and Congress over the president’s long-promised border wall.

The lieutenant governor will be back in Texas on Wednesday.

The White House did not immediately return a request for comment.

Patrick has long been a staunch supporter of the president, and served as the Texas chairman of Trump’s 2016 presidential run. And he has long been a vocal advocate of the border wall at the center of this year’s ongoing federal government shutdown. Trump is scheduled to address the nation later this evening, and set to travel to the border later this week.