AT LEAST four foreigners including three Americans were trapped inside a Kabul guesthouse yesterday after a group of Taliban gunmen laid siege to the building.

A Reuters witness at the scene saw about 20 people who appeared to be non-Afghans being evacuated from the guesthouse in an upmarket residential area of the capital, many looking frightened and in shock.

Roots for Peace, a US-based aid group, said that four people were trapped in its guesthouse, which was still under attack.

"I can confirm it was attacked and that there are only four people (inside)," said country manager Hajji Mohammad Sharif Osmani. "The rest of the guys are outside," he said.

A gun battle erupted after a Taliban suicide bomber blew himself up outside the building and insurgents forced their way in, before heavy gunfire was heard.

Kabul is on high alert and people are on edge ahead of next week's presidential election which the Taliban have vowed to disrupt.

Deputy interior minister, General Ayoub Salangi, said that at least one Australian was among those rescued.

Kabul police chief Mohammad Zahir said three US citizens, a Peruvian, a Malaysian and one unidentified African were still inside.

The Taliban immediately claimed responsibility,.