British citizens in Yemen must leave the country on commercial fights as soon as possible to avoid being stuck up amid escalating violence in the Gulf state, Foreign Secretary William Hague has warned, a report in The Telegraph stated on Saturday.

Mr Hague said, the British Government would not be able to evacuate UK nationals to safety as clashes between the regime of President Ali Abdullah Saleh and opposition tribesmen has intensified.

Rockets rained down on the presidential palace on Friday, killing seven guards and wounding the president and eight senior officials.

Hundreds of Britons are still believed to be in Yemen and he told the British nationals, not to expect from the government to be able to get them out of the country safely. He insisted them on leaving by commercial flights, before the airlines stopped flying to the country.

Today's extremely serious escalation of violence in Yemen underscores our clear message that British nationals in Yemen should leave immediately while commercial flights are still operating, he said on Friday night, said the report.

Given that we cannot expect forewarning of any airport closures, British nationals should not wait to leave. The British Government has been advising British nationals to leave Yemen since March 12 and we will not be in a position to evacuate those who do not leave on commercial airlines while these are still flying. I ask those in the UK with friends and relatives in Yemen to pass this message on and tell them to leave now. You should not plan for nor expect the British Government to be in a position to assist you to reach safety he said, The Telegraph report stated.

President Saleh, who suffered minor injuries in an attack on the presidential palace, delivered a defiant speech, wherein he blamed the attack on an outlaw gang.

The White House termed the violence senseless and called on all sides to cease hostilities and pursue a peaceful process of transferring power.