The United States has weighed into Universiti Malaya's (UM) action against its students for protesting against President Barack Obama, saying that there was "no reason" to do so for  expressing their rights.

US ambassador to Malaysia, Joseph Y Yun, said the  protest at Obama's town hall meeting organised by the embassy and hosted at UM was "brief and peaceful".

"The United States found no reason to raise the matter with the university nor to ask the university to investigate it with the students involved.

"United States firmly supports the rights to free of expression and association, including the right to peaceful protest without fear of reprisal," he said in a letter that was carbon copied to UM vice-chancellor Mohd Amin Jalaludin.

The letter, dated March 21, was in response to a correspondence by the UM Student Representative Council (SRC).

The SRC had raised the university's show-cause letter against four students who had held up anti-Trans Pacific Partnership Agreement (TPPA) placards at the meeting.

The university's SRC deputy president Lee Jin Yang who disclosed the letter said he was appreciative of the US’ positive gesture towards the students.

'US embassy willing to meet students'

"When we are protesting for the sake of Malaysians, UM is trying to charge us while the US is supporting us. We feel sad about this," he said.

Lee ( right ) added that UM has to improve its campus democracy and the Universities and University Colleges Act (UUCA) has to be abolished if it really wants to be ranked among the top universities in the world.

In the letter signed by Yun, the ambassador also said the US embassy staff are willing to meet with the students on the ongoing TPPA negotiations.

Show-cause letters were issued by the UM Student Affairs Department to the four who protested the town hall meeting with the Young Southeast Asian Leadership Initiative (Yseali).

They were accused of breaking the rules and damaging the interests and image of the institute.

The four are Lee, student council secretary Fahmi Zainol, assistant secretary Leong Yu Sheng and committee member Anis Nabihah Alias.