Saboteurs blew up a section of Yemen's main oil pipeline on Friday, partly disrupting output, the defence ministry and a local official said.
The attack struck in the Sarwaj district of Marib province, east of the capital, the ministry said in a statement.
A local official told AFP that engineers had been sent to the area to try to restore the flow of oil on the 320-kilometre (200-mile) pipeline from the Safer field to the Red Sea port of Hodeida.
The pipeline has been hit repeatedly by saboteurs, with two attacks last month alone.
In December, the army launched an offensive against tribesmen suspected of being behind the attacks, sparking clashes in which 17 people were killed.
Electricity Minister Saleh Sumai has blamed loyalists of former president Ali Abdullah Saleh, who was forced to step down early last year after holding power in Sanaa since 1978.
According to official figures, lost production due to pipeline attacks in the east cost the government more than $1 billion in 2012, as oil exports fell by 4.5 percent.