French President Nicolas Sarkozy has reappointed trusted ally Francois Fillon as prime minister as he begins a ministerial reshuffle aimed at shoring up his position 18 months before the next presidential election.

Fillon, who has proved a steady and capable aide to the president in the more than three years since Sarkozy has been in power, said he would focus on employment and the economy.

Sarkozy said in June he would rejig his cabinet once his flagship pension reform was in place. The reshuffle comes at a time when Sarkozy is trying to shore up his core support base, address voter gloom over the economy and improve his dismal ratings before the 2012 election.

‘After three-and-a-half years of brave reforms, carried out despite a severe global economic and financial crisis, I am starting ... a new phase with determination which will allow our country to strengthen the growth of the economy to help jobs, promote solidarity and safeguard the security of all French people,’ Fillon said in a statement.

After a short period when commentators thought Fillon would be replaced, in recent days Sarkozy was widely expected to reappoint the man has been a key aide and who was behind the campaign that swept him to power in 2007.

The rest of the new cabinet, which is expected to be composed of on proven heavyweights of the ruling centre-right UMP party and avoid surprises, will be unveiled later today or on Monday, an official at Fillon's office said.

Fillon, met with Sarkozy at the of the presidential Elysee palace today.

Dominique Paille, spokesman for the UMP party, told iTele television it was more important for the country to continue with reforms in the works than have a change in direction.

‘Nicolas Sarkozy has not opted for a new course. He has said that the rest of his mandate, the 18 months that will run until spring 2012, would be dedicated to the pursuit of reforms,’ Paille said.

Sarkozy has emerged victorious from a drawn-out battle with unions over pension reform but remains deeply unpopular with approval ratings below 30%. Fillon is more popular with the electorate and is widely seen as competent.

Opposition politicians were quick to criticise Sarkozy for taking almost five months to decide on his reshuffle only to end up keeping the same prime minister.

‘This means in any case that the same politics will continue,’ Jean-Marc Ayrault, president of the opposition Socialist party in the National Assembly, told LCI television.

Fillon was elected to parliament in 1981 and since 1993 has held various government posts including heading the labour, social affairs, education and research, and post and telecommunications ministries.

As labour minister in 2003, he shepherded an important change to the pension system through parliament, despite union protests, obliging civil servants to contribute for as long as private sector employees to qualify for a pension.