Democratic efforts in Congress to take away nuclear first strike capabilities from President Donald Trump have received a rush of support from voters across the country worried that the president might order an attack in North Korea or elsewhere.

Roughly half a million people have signed a petition supporting a bill reintroduced by two Democrats that would require a declaration of war by Congress before the president could launch an unprovoked nuclear weapon. The president would still retain the power to launch a nuke if a foreign foe attacked first.

“While it is vital for the president to have clear authority to respond to nuclear attacks on the United States, our forces or our allies, no president should have the authority to launch a nuclear first strike without congressional approval,” Senator Ed Markey, who introduced the bill alongside Representative Ted Lieu, said at a press conference.

Next to Mr Markey and Mr Lieu were 28 file boxes filled with the petitions.

“As long as President Trump has a Twitter account, we need a nuclear no-first-use policy for the United States of America,” Mr Markey said.

Tensions between the US and North Korea have escalated recently following several recent missile tests ordered by Pyongyang. Mr Trump warned that “major” conflict is possible should North Korea not curtain its nuclear program.

The controversial orders Donald Trump has already issued Show all 9 1 /9 The controversial orders Donald Trump has already issued The controversial orders Donald Trump has already issued Trump and the media White House Press Secretary Sean Spicer takes questions during the daily press briefing Getty Images The controversial orders Donald Trump has already issued Trump and the Trans-Pacific Partnership Union leaders applaud US President Donald Trump for signing an executive order withdrawing the US from the Trans-Pacific Partnership negotiations during a meeting in the Roosevelt Room of the White House in Washington DC. Mr Trump issued a presidential memorandum in January announcing that the US would withdraw from the trade deal Getty The controversial orders Donald Trump has already issued Trump and the Mexico wall A US Border Patrol vehicle sits waiting for illegal immigrants at a fence opening near the US-Mexico border near McAllen, Texas. The number of incoming immigrants has surged ahead of the upcoming Presidential inauguration of Donald Trump, who has pledged to build a wall along the US-Mexico border. A signature campaign promise, Mr Trump outlined his intention to build a border wall on the US-Mexico border days after taking office Getty Images The controversial orders Donald Trump has already issued Trump and abortion US President Donald Trump signs an executive order as Chief of Staff Reince Priebus looks on in the Oval Office of the White House. Mr Trump reinstated a ban on American financial aide being granted to non-governmental organizations that provide abortion counseling, provide abortion referrals, or advocate for abortion access outside of the United States Getty Images The controversial orders Donald Trump has already issued Trump and the Dakota Access pipeline Opponents of the Keystone XL and Dakota Access pipelines hold a rally as they protest US President Donald Trump's executive orders advancing their construction, at Columbus Circle in New York. US President Donald Trump signed executive orders reviving the construction of two controversial oil pipelines, but said the projects would be subject to renegotiation Getty Images The controversial orders Donald Trump has already issued Trump and 'Obamacare' Nancy Pelosi who is the minority leader of the House of Representatives speaks beside House Democrats at an event to protect the Affordable Care Act in Los Angeles, California. US President Donald Trump's effort to make good on his campaign promise to repeal and replace the healthcare law failed when Republicans failed to get enough votes. Mr Trump has promised to revisit the matter Getty Images The controversial orders Donald Trump has already issued Donald Trump and 'sanctuary cities' US President Donald Trump signed an executive order in January threatening to pull funding for so-called "sanctuary cities" if they do not comply with federal immigration law AP The controversial orders Donald Trump has already issued Trump and the travel ban US President Donald Trump has attempted twice to restrict travel into the United States from several predominantly Muslim countries. The first attempt, in February, was met with swift opposition from protesters who flocked to airports around the country. That travel ban was later blocked by the Ninth Circuit Court of Appeals. The second ban was blocked by a federal judge a day before it was scheduled to be implemented in mid-March SANDY HUFFAKER/AFP/Getty Images The controversial orders Donald Trump has already issued Trump and climate change US President Donald Trump sought to dismantle several of his predecessor's actions on climate change in March. His order instructed the Environmental Protection Agency to reevaluate the Clean Power Plan, which would cap power plant emissions Shannon Stapleton/Reuters

Limiting the president’s blanket authority to launch a nuclear weapon has been debated for a long time by those concerned that a president might make a call that leads to nuclear warfare without due care. There are virtually no checks on the president’s authority to order a nuclear missile launch — a policy supported by individuals who argue that the timeframe of a nuclear attack against the US would require the president to respond quicker than he would be able to if he needed to check in with Congress first.

Former President Barack Obama weighed the option of changing the office’s first strike policy but decided against it on the advice of officials.