Sen. Marco Rubio wants Ambassador Nikki Haley to seek an emergency session on Venezuela in the United Nation’s Security Council.

The Florida Republican wants the Trump administration to ratchet up its pressure on the international body to take more aggressive steps to counter deteriorating conditions in the South American country.

“It is clear that the United States can — and should — do more to increase international pressure against Maduro and his cronies,” Rubio wrote in a letter to President Trump, co-written with Democratic Sen. Bob Menendez of New Jersey.

Rubio, who has the ear of President Donald Trump on Latin America issues, is kicking off 2018 by increasing his office’s pressure on the U.S. government to take greater action on Venezuela, including calling for additional sanctions against some of the country’s most powerful leaders. Earlier this week, Rubio pressed Trump to issue sanctions against Diosdado Cabello, who is seen as Venezuela’s second most powerful leader and head of the ruling socialist party.

The once-mighty nation sitting on the world’s largest oil reserves has plummeted into a deepening economic crisis amid rising inflation. In recent months, anti-government demonstrations have broken out as desperate citizens take to the streets to protest the lack of even the most basic goods.

The Trump administration has been increasing pressure on Caracas since Venezuelan President Nicolás Maduro engineered a vote last year for a new constituent assembly that stripped democratically elected lawmakers of their power.

Sanctions have been imposed more than 20 current and former Venezuelan government officials in recent months, including President Nicolas Maduro. The administration has also restricted Venezuela’s ability to borrow money from U.S. banks and creditors.

While praising the attention that the administration’s paid to Venezuela in 2017, the two Senators want to make sure that the administration doesn’t let up. They also want Trump to use his influence and pressure to make sure Secretary of State Rex Tillerson keeps Venezuela at the top of the State Department agenda.

“This lawless environment threatens the stability and security of the region, including the United States, by providing fertile ground for drug cartels and U.S.-designated foreign terrorist organizations, such as the FARC and ELN, to operate,” Rubio and Menendez wrote.

In the letter released Thursday, Rubio seeks help from Haley, a 2016 political ally. During the GOP presidential primaries two years ago, Haley, then the governor of South Carolina, endorsed Rubio days before that state’s primary. Trump still won the primary, but Haley’s endorsement boosted Rubio into a second place finish.