A new poll conducted by NBC News and the Wall Street Journal this week found that US President Barack Obama's approval rating continues to be at its lowest yet. 54% disapprove of Obama's job as president, the highest that figure has ever been.

The poll, conducted among 1000 respondents, found that 58% disapprove of Obama's handling of the economy, and in particular that Americans are critical of Obama's new health care law, commonly termed "Obamacare."

Among other problems, Obamacare has caused "sticker shock", as insurance prices have soared and many Americans have been left without coverage. Some have charged that the president knowingly lied to the American public when he infamously promised "if you like your plan you can keep it."

Half of the respondents to the new poll said Obamacare is a bad idea, with 54% saying the new law has a negative impact on national healthcare. Furthermore, 58% say the law is the most important issue shaping their opinion of Obama's presidency.

As far as his traits as president, Obama is viewed with increasing criticism. His rankings are down in several areas, as only 28% gave him high grades for being able to achieve his goals, and only 37% consider him honest and straightforward.

“These are tough and sobering numbers for the president and his administration,” according to Democratic pollster Fred Yang, who carried out the survey with Republican pollster Bill McInturff.

Congress came in for criticism on the poll as well, with 51% of respondents saying that this year was one of the worst in terms of congressional performance.

Meanwhile Fox News reports that a Quinnipiac University national poll released Tuesday found Obama's job approval score is currently at a new low of 38%. The poll also found that a majority of 41% said they would vote for Republicans over Democrats in House of Representatives elections, suggesting Obama's negative impact on his party in general.

Obama recently caused an uproar by shaking Cuban President Raul Castro's hand at an event commemorating Nelson Mandela. Republicans were quick to condemn the conciliatory gesture, which came as the communist regime in Havana continues to hold American contractor Alan Gross, who this month marked four years in prison in Cuba.

Gross was jailed for 15 years for distributing communications equipment to Cuba's tiny Jewish community.

Speaking to ABC News, Senator Marco Rubio, whose parents left Cuba three years before Raul's brother and predecessor Fidel Castro took power, said that Obama "should have asked him about those basic freedoms Mandela was associated with that are denied in Cuba."

Other Republicans went even further, comparing it to Europe's appeasement of Nazi Germany during the 1930s.