British special forces have been sent to Libya in a bid to halt the advance of the Islamic State, it has been reported.

SAS troops are understood to be preparing for an offensive involving 1,000 British soldiers to wrest back control of a dozen oil fields seized by the jihadists.

ISIS has taken advantage of the lawlessness since the 2011 ouster of Colonel Gaddafi to make large gains along the coastline, setting up its power base in the former dictator's hometown of Sirte.

Mirroring its strategy in Iraq and Syria, the terror group has seized a number of revenue-boosting oil fields and are now targeting the Marsa al Brega refinery, the biggest in North Africa.

SAS troops are understood to be planning an offensive involving 1,000 British troops to seize back control of oil fields captured by the Islamic State in Libya after the country descended into chaos (file picture)

In an attempt to stop the advance, a major coalition offensive is planned within the next few weeks or months, it was reported by The Daily Mirror.

The operation will involve around 6,000 U.S. and European soldiers led by Italian forces, the SAS and military close observation experts from the Special Reconnaissance Regiment.

British experts will advise Libyan military commanders on so-called 'battle-space management' – tactics and skills needed to control the battlefield.

They will also send intelligence back to MoD chiefs that could be used to determine whether airstrikes are needed.

A senior military source told the Mirror: 'This Coalition will provide a wide range of resources from surveillance, to strike operations against Islamic State who have made significant progress in Libya.

'We have an advance force on the ground who will make an assessment of the situation and identify where attacks should be made and highlight the threats to our forces.'

Show of force: ISIS released a propaganda video last month from Libya, showing off their Islamic police force which are shown patrolling around the city of Sirte, the hometown of former dictator Colonel Gaddafi

As the heart of the ISIS caliphate in Syria and Iraq shrinks, Firas Abi Ali, Middle East analyst at research firm IHS, has predicted ISIS would likely see oil-rich Libya as a 'plan B' and expand there.

He said: 'Moreover, the ideologies of jihadism and of political Islam are alive and well. It is far too soon to write off Islamic State and organisations similar to it.'

Libya has been in chaos since the 2011 ouster of Gaddafi and now has two governments and parliaments.

Jihadist groups such as the Islamic State have made gains along the coastline and the UN estimates that fighting has forced 435,000 people from their homes.

Meanwhile, the UN's envoy for Libya held talks in Tripoli Friday, seeking to encourage the administration there to commit to a national unity government that would end years of bloodshed.

ISIS has taken advantage of the lawlessness since the 2011 ouster of Gaddafi to make gains along the coast

Martin Kobler, on a desperate diplomatic push to get Libya's two separate administrations to sign a power-sharing agreement, met on Thursday with representatives of the internationally-recognised government near its headquarters in the east of the country.

On December 17, under UN guidance, envoys from both sides and a number of independent political figures signed a deal to unify the government.

Around 80 of 188 lawmakers from Libya's internationally recognised parliament and 50 of 136 members of the rival Tripoli-based General National Congress signed the deal.

It calls for a 17-member government, headed by businessman Fayez el-Sarraj as premier, based in Tripoli.