LISBON (AFP) -- Portuguese construction firms are piling up business in Angola, where soaring oil exports and a massive loan from China are fueling a reconstruction boom following the end of a 27-year civil war.

Builders were a key part of a trade mission that accompanied Portugal's Prime Minister Jose Socrates last week during his four-day official visit to Angola, which gained independence from Lisbon in 1975.

Portugal's construction firms expanded during an economic boom in the late 1990s but sluggish economic growth in Portugal in recent years has left them with excess capacity that can be employed in the African country, said private bank BPI chief economist Cristina Casalinho.

"Angola is an interesting alternative to investments in other countries, like in eastern Europe, where entry costs are higher and the prospect of gains is more limited," she told AFP.

Portuguese firms also enjoy competitive advantages in Angola, such as a common language, a similar legal system and often previous experience in the country, said Casalinho, who covers the Angolan economy for BPI.

While spending on public works projects is down in Portugal as it strives to contain a ballooning public defict, Angola has opened up its coffers to rebuild roads, bridges and other infrastructure since a peace deal signed in 1975 paved the way for reconstruction.

The Angolan government, flush with funds due to the rising price of oil, set aside 1.1 billion dollars (910 million euros) in 2005 to spend on public works and plans to invest another 788 million dollars million dollars this year.

Many more public works projects are being financed by a two billion dollar oil-backed loan that China gave Angola in 2004.

Angola replaced Saudi Arabia in February as China's largest oil supplier.

Three major Portuguese construction firms -- Somague, Mota-Engil and Soares da Costa -- are all preparing tenders for a contract to build a new port in the Angolan capital Luanda, a project worth over 100 million euros.

Soares da Costa, which has operated in Angola for over two decades, expects the country will account for nearly half of its overall turnover this year.

The company plans to move into areas outside of Luanda this year to take advantage of the opportunities created by an economic growth rate that the government expects will hit 27 percent, company officials have said.

Soares da Costa's turnover in Angola reached 137 million euros last year and the company has a portfolio of work in the country worth 300 million euros, the firm's president, Pedro Goncalves, told the Lusa news agency last month.

The firm is currently building the new headquarters of Angolan state oil giant Sonangol in Luanda in a consortium with South Africa's Grinaker and is working on the giant Torres Atlantico office complex in the Angolan capital along with Mota-Engil.

Mota-Engil, Portugal's largest contruction firm, is currently building the new heaquarters for Angola's health ministry and immigration department, as well as several stretches of highway.

"We have the know-how in Portugal to help develop Angola's economy," the president of the firm, Antonio Mota, told reporters while on a visit last week to a new four-lane highway Mota-Engil is buidling in central Angola. Angola accounted for 13 percent of Mota-Engil's total turnover of 1.4 billion euros last year

The success of long-established builders like Mota-Engil and Soares da Costa has attracted new players to the country.

Portuguese contruction firm Edifer and Angolan company Gema signed an agreement to develop real estate projects in Angola last week during Socrates' visit to the southwest African country.

Chinese state construction giant COVEC meanwhile is seeking to form partnerships with Portuguese firms to work on insfrastructure projects in Angola where it is stepping up its activity.

"It is a possibility to be considered because the language barrier sometimes causes difficulties," the firm's deputy director-general, Shi Ping, was quoted as saying in February in Beijing.

Portuguese construction firms have in the past experienced lengthy delays in getting paid by the Angolan government for public works projects they complete.

And, privately, representatives of builders and other firms complain of corruption in a nation where more than 70 percent of its 14 million people live in grinding poverty. But despite these obstacles, Portuguese officials remain enthusiastic about the Angolan economy

"It would be a sin if we did not take advantage of these exceptional conditions," Economy Minister Manuel Pinho told reporters at the end of Socrates' visit to Angola.