Lawmakers on Sunday urged President Trump Donald John TrumpBubba Wallace to be driver of Michael Jordan, Denny Hamlin NASCAR team Graham: GOP will confirm Trump's Supreme Court nominee before the election Southwest Airlines, unions call for six-month extension of government aid MORE to take action in response to a reported chemical attack in Syria that comes as Trump pushes for a draw down of U.S. troops in the war-torn nation.

Senators in both parties pressed Trump to act amid reports that at least 70 individuals are dead in the Syrian city of Douma. Meanwhile, the president in a rare tweet called out Russian President Vladimir Putin for his role in Syria’s ongoing civil war that just entered its eighth year.

But Trump has sent mixed signals about his likely response to Syria, advocating getting the U.S. out of the conflict there but also on Sunday tweeting criticism of his predecessor President Obama's hands-off response to a similar situation.

Following Trump's Sunday tweets, Sen. John McCain John Sidney McCainBiden's six best bets in 2016 Trump states Replacing Justice Ginsburg could depend on Arizona's next senator The Hill's Morning Report - Sponsored by Facebook - Washington on edge amid SCOTUS vacancy MORE (R-Ariz.), who has long advocated U.S. military action in Syria, issued a statement in which he urged the president to respond to the alleged chemical attacks.

"Trump was quick to call out [Syrian President Bashar] Assad today, along with the Russian and Iranian governments, on Twitter," McCain said. "The question now is whether he will do anything about it."

The senator noted that Trump had responded with military force against Assad's forces following similar reports last year.

"He should do so again, and demonstrate that Assad will pay a price for his war crimes," McCain said.

Other lawmakers on Sunday pushed for the administration to do more as well.

“Clearly there needs to be a response, it needs to be an international response,” Sen. Ben Cardin Benjamin (Ben) Louis CardinCongress must finish work on popular conservation bill before time runs out PPP application window closes after coronavirus talks deadlock Congress eyes tighter restrictions on next round of small business help MORE (D-Md.), a member of the Senate Foreign Relations Committee, told CBS’s “Face the Nation.”

The State Department, in its initial response on Saturday, also said the attacks "demand an immediate response by the international community.‎"

Sen. Lindsey Graham Lindsey Olin GrahamGraham: GOP will confirm Trump's Supreme Court nominee before the election Fox's Napolitano: Supreme Court confirmation hearings will be 'World War III of political battles' Grassley, Ernst pledge to 'evaluate' Trump's Supreme Court nominee MORE (R-S.C.), who sits on the Senate Armed Services Committee, echoed Cardin, but also advised Trump to stay the course in Syria, arguing a United States departure would empower groups like the Islamic State in Iraq & Syria and Hezbollah.

“But President Trump can reset the table here. To me, I would destroy Assad's air force,” Graham told ABC’s “This Week."

“I would create safe zones in Syria where people can come back to their country from the surrounding area and live a better life. Train up Syrians to take on Assad so we can negotiate in Geneva from a position of strength.”

White House homeland security adviser Tom Bossert on Sunday maintained that nothing is “off the table” in regard to Syria.

But the most recent chemical attack follows the president’s public pledge late last month to get U.S. troops out of Syria “very soon.”

"Let the other people take care of it now. Very soon. Very soon, we're coming out. We're going to have a hundred percent of the caliphate, as they call it. Sometimes referred to as land, taking it all back. Quickly, quickly," Trump told a crowd in Ohio on March 29.

The remarks put the president at odds with his military advisers, who worry the absence of U.S. forces could lead to a vacuum for terrorist groups in a country ravaged by civil war.

“I think the president is going to have to reconsider his plan for an early withdrawal, in light of what has happened,” Sen. Susan Collins Susan Margaret CollinsGraham: GOP will confirm Trump's Supreme Court nominee before the election Gardner signals support for taking up Supreme Court nominee this year Tumultuous court battle upends fight for Senate MORE (R-Maine) told CNN’s “State of the Union.”

House Minority Leader Nancy Pelosi Nancy PelosiTrump puts Supreme Court fight at center of Ohio rally CDC causes new storm by pulling coronavirus guidance Overnight Health Care: CDC pulls revised guidance on coronavirus | Government watchdog finds supply shortages are harming US response | As virus pummels US, Europe sees its own spike MORE (D-Calif.) also weighed in on Sunday, saying that Putin must be held responsible for backing Assad.

“Members of Congress expect a comprehensive intelligence briefing on this attack as soon as possible," Pelosi said in a statement. "The Trump Administration must finally provide a smart, strong and consistent strategy in Syria.”

Trump's move to withdraw from Syria aligns with his "America-first" foreign policy as well as the response he advocated on Syria in 2013, when he urged Obama not to react to reported chemical weapon use there.

"President Obama, do not attack Syria. There is no upside and tremendous downside. Save your 'powder' for another (and more important) day!" he tweeted then.

Still, Trump on Sunday attacked Obama for failing to deal with Syria during his term in office, tweeting, "if President Obama had crossed his stated Red Line In The Sand, the Syrian disaster would have ended long ago!"

Obama had said in 2012 that Syria using chemical weapons would cross a "red line" with the U.S. However, in 2013 he chose to negotiate along with Russia a deal for Syria to give up its weapons.

Trump has previously responded militarily to reported chemical weapons use. The most recent reported attack comes almost one year to the day since Trump ordered the U.S. military to launch Tomahawk missiles at a Syrian airfield believed to be the launching point of a deadly chemical weapons attack last April.

The Syrian government denied a role in the most recent attack through state media on Sunday, as did the Russian foreign ministry. While the source of the suspected chemical attack has yet to be named, the city of Douma is home to rebel fighters battling the Syrian government.

Trump publicly accused Putin on Twitter of backing Assad, who has received political and military support from Moscow throughout the civil war.

“Many dead, including women and children, in mindless CHEMICAL attack in Syria. Area of atrocity is in lockdown and encircled by Syrian Army, making it completely inaccessible to outside world,” Trump said. “President Putin, Russia and Iran are responsible for backing Animal Assad.”

The White House said Trump discussed the reported attack with Iraqi Prime Minister Haider Al-Abadi in a phone call on Sunday.

Republican Sen. Mike Rounds Marion (Mike) Michael RoundsChamber of Commerce endorses McSally for reelection Senate GOP eyes early exit Senate Republicans signal openness to working with Biden MORE (R-S.D.) said in an interview that he believes Trump will hold both Syria and Russia accountable for the recent attack.

“I think he will hold not just Syria, but I think he will make it very clear that he believes that Russia is also responsible,” Rounds told NBC’s “Meet the Press.”

Cardin, who said Trump’s tweet referencing Putin by name constituted “a significant change,” also said Assad should be held responsible. Although the State Department often meets Russia with firm rhetoric, Trump has been notably less direct with Putin.

“Well first and foremost President Assad needs to be held accountable for his war crimes,” Cardin said Sunday.

Speaker Paul Ryan Paul Davis RyanKenosha will be a good bellwether in 2020 At indoor rally, Pence says election runs through Wisconsin Juan Williams: Breaking down the debates MORE (R-Wis.) on Sunday also said Assad must be held accountable for the suspected attack.

“The chemical attack in Syria is a horror that cannot be tolerated by responsible nations,” Ryan said on Twitter. “The U.S. must continue to lead an international effort to hold the Assad regime and Russia accountable for their actions.”

Updated: 4:26 p.m.