SANAA, March 2 (Xinhua) -- Yemen's former President Ali Abdullah Saleh, who is the main ally with Shiite Houthi rebels, called the Yemeni army on Thursday to join Houthi fighters in border fighting against Saudi forces.

The call, which was aired by Houthi-controlled state media, signaled Yemen's further escalating military tension with neighboring Saudi Arabia, which led a military coalition of mostly Arab countries in support to exiled Yemeni President Abd-Rabbu Mansour Hadi against Houthi rebels.

"I call the defense ministry to mobilize armed forces to front lines to reinforce popular forces (Houthis) in border battlefronts against Saudi forces," Saleh said in a speech in a meeting with senior leaders of his former ruling party, the General People's Congress.

The defense ministry has been under Houthi control since Houthis seized the capital Sanaa in September 2014.

However, the Yemeni national army has stayed neutral since then and also remained neutral after Houthis ousted internationally recognized President Hadi and forced him along with his government into exile.

In his speech, Saleh also renewed his call to not conduct further peace talks with exiled President Hadi and his government, describing them as "mercenaries."

The move clearly indicates further military escalation, particularly after repeated rounds of peace talks mediated by the United Nations have failed.

Saleh's move came as battles on the border intensified over the past days, in which Saudi military forces have been trying to advance into the Yemeni northern province of Saada, the main stronghold of Houthi group and its religious leader Abdul Malik al-Houthi.

Saudi-led coalition also mobilized forces and fighters loyal to Hadi's government off Red Sea port cities of neighbouring Hodeidah and Mokha in a bid to set siege on capital Sanaa, the second stronghold of Houthis and Saleh loyalists.

Saleh was forced out of power in 2012, following a year of popular protests, led by Muslim Brotherhood, which later allied with President Hadi.

Houthi fighters, who seized control of north Yemen, have been fighting Saudi Arabia on borders since the Saudi-led military coalition intervened in the Yemeni conflict in March 2015 via an air and ground campaign.

The campaign is attempting to restore power to expelled President Abd-Rabbu Mansour Hadi. More than 10,000 Yemenis have been killed, with over three million displaced.