Rashida Tlaib, the first Palestinian-American congresswoman, is accused of anti-Semitism for questioning Republican lawmakers' loyalty to Israel over the US.

'They forgot what country they represent,' Tlaib said of Republican lawmakers in a tweet Sunday while objecting to a proposed bill in the Senate that would punish American companies for participating in the anti-Israel Boycott, Divestment and Sanctions (BDS) campaign.

'This is the US where boycotting is a right & part of our historical fight for freedom & equality. Maybe a refresher on our U.S. Constitution is in order, then get back to opening up our government instead of taking our rights away,' she added, in response to a post by Senator Bernie Sanders.

Both of their posts criticized Senate Republicans for introducing the pro-Israel bill Strengthening America's Security in the Middle East Act of 2019, instead of proposing legislation to end the now 17-day government shutdown.

Republic lawmakers, including Senator Marco Rubio, were quick to label Tlaib as anti-Semitic for suggesting Republicans' loyalty lies with Israel - a notion known as 'dual loyalty' which traces back hundreds of years to anti-Jewish attacks.

Rashida Tlaib, the first Palestinian-American woman elected to congress, criticized a proposed bill by Republican that would impede Americans from participating in the anti-Israel BDS movement

She tweeted that Senate Republicans 'forgot what country they represent'

Tlaib has been bashed by Senator Marco Rubio, who labeled her remarks anti-Semitic

The BDS movement is a global boycott of all things Israeli which states its purpose is to end international support for Israel's oppression of Palestinians and pressure Israel to comply with international law.

One of the bills in the package is called the Rubio-Manchin Combating BDS Act of 2018, meant to limit the BDS movement in the US.

It states it would 'increase protections for state and local governments in the United States that decide to divest from, prohibit investment in, and restrict contracting with companies knowingly engaged in commerce-related or investment-related BDS activity targeting Israel,' according to Senate Republicans.

Critics of the bill claim that it is unconstitutional and violates the First Amendment.

Bernie Sanders tweeted Sunday: 'It’s absurd that the first bill during the shutdown is legislation which punishes Americans who exercise their constitutional right to engage in political activity. Democrats must block consideration of any bills that don’t reopen the government. Let's get our priorities right.'

To which Senator Marco Rubio tweeted: 'This is a lie. My bill doesn’t punish any political activity. It protects the right of local & state govts that decide to no longer do business with those who boycott #Israel. So boycotting #Israel is a constitutional right, but boycotting those participating in #BDS isn’t?'

The Boycott, Divestment and Sanctions (BDS) campaign seeks to end international support for Israeli's oppression of Palestinians

Tlaib told supporters at a party hosted by the liberal MoveOn group that 'we're going to impeach the motherf***er' about President Trump

Rubio went on to comment on Tlaib's tweet, saying: 'This “dual loyalty” canard is a typical anti-Semitic line. #BDS isn’t about freedom & equality, it’s about destroying #Israel.

'And if boycotting #Israel is constitutionally protected, then boycotting companies that boycott #Israel is also constitutionally protected.'

Tlaib later hit back at Rubio, saying: 'Sen. Rubio, it's clear my earlier tweet was critical of U.S. Senators like yourself, who are seeking to strip Americans of their Constitutional right to free speech.'

The Anti-Defamation League released a statement in response to Tlaib's tweet: 'Representative Tlaib's tweet regarding the pending bill on the Senate floor has been interpreted by some as suggesting that Jews or Members of Congress, such as the sponsors of the bill, are more loyal to Israel than to their own country,' the organization said. 'Whether or not this was her intent, this type of language is deeply problematic.'

This is the second hit Tlaib has gotten since being sworn in as one of the first Muslim women elected to Congress.

On Thursday night, she dropped the F-bomb at the president during a party hosted by the liberal group MoveOn.

Speaking in a dimly lit room, Tlaib told a cheering crowd that she had told one of her young sons: 'We're going to impeach the motherf***er!'

Republican House Minority Leader Kevin McCarthy blasted her on Friday and slapped at House Speaker Nancy Pelosi for not publicly disavowing the slur.