Top oil exporter Saudi Arabia and Gulf Opec ally Kuwait will beef up security around their oil facilities, they said, after they and other Arab allies began a military operation in Yemen.

Warplanes from Saudi Arabia and Arab allies struck Shi'ite Muslim rebels fighting to oust Yemen's president on Thursday, in an attempt by the regional heavyweight to check Iranian influence in its backyard without direct military backing from Washington.

Oil prices rallied on Thursday after the air strikes in Yemen, on the borders of Saudi Arabia, sparking fears of a wider Middle East conflict that could disrupt world crude supplies. Benchmark Brent was up $2.30, or four per cent, at $58.78 a barrel.

In a statement carried by state news agency SPA Deputy Crown Prince Mohammed bin Nayef, who is also Saudi Arabia's interior minister, stressed the importance of "strengthening all security measures on the borders of the kingdom and in all public utilities and around the oil and industrial facilities".

Opec Gulf member Kuwait said earlier on Thursday it had raised security around its oil facilities inside and outside the country after the military operation.

"In the light of developments in Yemen and to protect the strategic interests of the oil sector and securing oil products for inside and outside several procedures and precautionary steps taken," official news agency Kuna quoted state-run Kuwait Petroleum Corp. acting Chief Executive Officer Mohammad Al-Farhoud as saying.

The US Energy Information Administration estimates that Yemen's crude oil production was about 100,000 barrels per day (bpd) in March 2014. The country exports about 1.4-1.5 million barrels of Masila crude each month, mainly to China.

Most of Yemen's production is in the Marib-Jawf area in central Yemen and near the Masila area in the east.

French oil company Total is the biggest foreign investor in Yemen and operates the Balhaf gas export facility, which mainly exports natural gas to Asia and Europe.

Total said its sites in Yemen had not been impacted by the military action in the country and that its offices in the Yemeni capital, Sanaa, were closed.

Yemen shut its major seaports on Thursday, industry and local sources said. - Reuters