British Foreign Secretary William Hague said Sunday there is no deadline for NATO\'s Libya operation, as Russia voiced concerns that the use of helicopters showed it was sliding towards a land campaign. As British Apache choppers attacked forces loyal to Libyan leader Moamer Kadhafi for a second night, Hague admitted the nearly three-month-old mission was \"intensifiying\" but denied any \"mission creep\". \"We\'re not going to set a deadline. You\'re asking about Christmas and who knows, it could be days or weeks or months, (but) it is worth doing,\" Hague told an interviewer on BBC television. \"If we were not doing this Kadhafi would have overrun by force the whole of Libya, causing a massive humanitarian crisis, committing many atrocities and destabilising Tunisia and Egypt at the same time, with terrible consequences for Europe and this country.\" Hague, who held talks with Libyan rebel leaders in their stronghold Benghazi on Saturday, ruled out putting ground forces, saying NATO would stick to the terms of a UN Security Council resolution passed in March to protect civilians. \"We will continue in that way, intensifiying what we\'re doing -- the Apache helicopters are an example of that -- but that\'s different from mission creep,\" the foreign secretary said. \"This is not mission creep, changing the nature of the mission, this is intensifiying what we are doing in order to make this mission a success,\" he added. His comments came as the defence ministry said British Apaches based on HMS Ocean off the north African coast had destroyed a multiple rocket launcher near the eastern Libyan oil hub of Brega on Saturday. British Tornado strike planes separately joined other NATO aircraft in a major strike in Tripoli. Moscow, which is calling for a negotiated solution to the conflict, expressed alarm on Saturday and Foreign Minister Sergei Lavrov said the decision to use helicopters was \"deplorable\". \"We consider that what is going on is either consciously or unconsciously sliding towards a land operation,\" Lavrov said.