U.S. President Barack Obama has asked his Yemeni counterpart Ali Abdullah Saleh to deliver on his pledge of reforms with "concrete actions," the White House said on Thursday.

Obama welcomed the "significant reform measures" announced by Saleh in a phone call on Wednesday, and stressed that pledge must be followed up with concrete actions, the White House said in a statement.

Facing popular protests seeking an end to his rule of more than 30 years, Saleh pledged in parliament on Wednesday that he will not seek another term or hand his power to his son. He also promised to achieve more political and economic reforms.

Over 20,000 Yemenis took to the streets of the capital city of Sanaa on Thursday for a "Day of Rage" march, demanding Saleh's resignation.

In his call to Saleh, Obama asked that Yemeni security forces show restraint and refrain from violence against the demonstrators. The U.S. president stressed as well that it is imperative that Yemen take forceful action against al-Qaida in the Arabian Peninsula (AQAP) to protect innocent lives in Yemen as well as abroad, the White House said.

The U.S. has boosted aid to Yemen in its fight against the AQAP following a foiled parcel bomb plot against U.S. targets in October.