Libya is a "major concern" for terrorism, migration and regional stability, the Prime Minister's National Security Adviser has told parliamentarians.
The comment came as Downing Street insisted that no decision had been taken on whether to deploy UK troops in any international military intervention in the north African state.
The US and French governments have been pressing for direct action against the Islamic State terror group - also known as Daesh, Isil or Isis - in Libya, where it has established around the city of Sirte amid the chaos following the overthrow of former ruler Muammar Gaddafi in 2011.
Asked about press reports that the UK was considering sending as many as 1,000 troops to the country, Prime Minister David Cameron's official spokeswoman said: "No decisions have been made about the deployment of any British forces to Libya as part of an international force."
The spokeswoman said that discussions were under way among Britain's international partners on how to support a viable Libyan national unity government. Agreement was reached in December on unifying two rival administrations in capital Tripoli, but this decision has yet to take effect.
National Security Adviser Sir Mark Lyall Grant confirmed that Libya was regularly discussed by the National Security Council chaired by Mr Cameron.
Sir Mark told the parliamentary Joint Committee on the National Security Strategy: "We have discussed Libya in the National Security Council certainly two or three times in the last six months.
"It is an issue of major concern in a number of different contexts - in the counter-terrorism context, the stability context and the migration context.
"When we discuss counter-terrorism, Libya is a feature. When we discuss migration, Libya is a feature. But we have also discussed Libya itself in terms of instability and the political progress. We take them into account on all of these issues.
"There is a regular, almost weekly, meeting chaired either by me or my deputy to look at the Libya situation. The Foreign Secretary regularly offers advice to the Prime Minister on Libyan policy, what the next step should be, and how we should react to developments."
Mr Cameron has said the UK will do "everything we can" to support a new Libyan government in its efforts to combat IS and the criminal gangs behind the migrant boats heading to Europe.
The Sunday Times claimed that RAF officers, MI6 operatives and diplomats joined US and French colleagues at an airbase in Tobruk controlled by pro-western militia forces to establish potential targets.