Pretoria, South Africa ? President Bush suggested Wednesday that any U.S. military help in ending brutal civil unrest in Liberia might consist mostly of advisers and trainers to avoid stretching American forces too thinly around the globe.

“We won’t overextend our troops, period,” Bush said at a joint news conference with South African President Thabo Mbeki, who had pressed him on what role the United States would play in the crisis.

African nations want the United States to do more to end the bloodshed in the western Africa nation. But U.S. lawmakers, including some leading Republicans, have questioned the wisdom of yet another major overseas military entanglement with so many troops already on the ground in Iraq, Afghanistan and elsewhere.

Still weighing a final decision, Bush noted that the Pentagon had already trained African peacekeepers, including those from Nigeria and Senegal.

“It’s in our interest that we continue that strategy so that we don’t ever get overextended,” he said.

Bush has invited U.N. Secretary-General Kofi Annan, the head of U.N. peacekeeping and the head of U.N. political affairs Monday to the White House, according to a United Nations official in Washington.

While it was not clear that Liberia was the topic, Annan has said in the past that he who would like to see the United States lead a multinational peacekeeping force there.

Anti-American protesters hold a banner to protest the visit to South Africa of U.S. President George W. Bush. Bush met Wednesday with his South African counterpart, Thabo Mbeki, in the Union Buildings in Pretoria, background. Bush was on the second leg of his five-nation African trip.

On the second leg of a five-nation Africa trip, Bush promoted his $15 billion, five-year plan to combat AIDS and proposals to increase trade with sub-Saharan Africa. His first stop was Tuesday in Senegal. Still ahead: visits to Botswana, Uganda and Nigeria.

Also on Bush’s agenda was the continuing strife in Zimbabwe, where there has been violence and economic upheaval aggravated by President Robert Mugabe’s refusal to pursue democratic reform. Bush appealed to Mbeki to step his pressure on Mugabe to restore democracy to South Africa’s neighbor in southern Africa.

In South Africa’s capital of Pretoria, about 1,000 demonstrators marched peacefully to the U.S. Embassy, protesting Bush’s war in Iraq and trip to Africa. About two dozen police officers and a handful of embassy employees looked on as demonstrators burned several small American flags emblazoned with slogans against Bush.

“We stand together with millions of people throughout the world and say that the biggest weapon of mass destruction is George W. Bush,” Salim Vally of the Anti-War Coalition said in a speech.

Bush is spending more time in South Africa than any other nation on his African trip. He toured a Ford automobile plant and attended a dinner for Mbeki at the home of U.S. Ambassador Cameron Hume.

But Bush was not scheduled to meet with former South African President Nelson Mandela, the popular leader and hero of the anti-apartheid struggle who had harshly criticized Bush for going to war without a U.N. mandate.