Kabul  - Afghan President Hamid Karzai and Pakistani Premier Asif Ali Zardari hailed improved relations between their nations Tuesday and vowed jointly to combat terrorism and extremism.

Zardari arrived in Kabul on a two-day trip and held talks with Karzai in the fortified presidential palace.

"We have a much better understanding between our two governments, between the two presidents than ever before - God is kind in this regard to us," Karzai told a joint press conference.

"We are discussing in depth on methods and actions to further enhance our struggle against extremism and terrorism," Karzai said.

Zardari said: "We want to tell the world today that we are standing shoulder to shoulder, that we are together in this fight against these non-state actors who have taken nations and countries, and in fact superpowers, to war."

In the fight against terrorism they were not "doing any or each other or anybody else a favour, but a favour to ourselves and the coming generations... so that our children can have a better Pakistan and a better Afghanistan and a better region."

Zardari, widower of Pakistan's former prime minister Benazir Bhutto, was elected president in September. Bhutto was killed in a suicide attack, allegedly carried out by Pakistan-based Taliban militants.

Unlike his predecessor General Pervez Musharraf, who was at daggers drawn over Karzai's accusations that Pakistan was supporting the insurgents in Afghanistan, Zardari has maintained good relations between Islamabad and Kabul.

During Musharraf's terms, Afghan officials including Karzai had repeatedly accused Pakistan of not doing enough to stop cross-border infiltration by Taliban militants who are said to have sanctuaries in Pashtun-dominated areas straddling the common border.

However, Zardari is also seen as more determined to fight the insurgency and has taken bold steps against rebels stationed on the border between the two countries since taking office.

"Since the inauguration of President Zardari's government we have not complained," Karzai said, adding "so thank you Mr President, because of you, we stopped complaining."

Pakistani forces recently mounted a major operation to root out the militants from around an highway that links Pakistan's Peshawar city to the Afghan border.

But Afghan and western military officials have indicated in the past that the militants would continue to operate in tribal areas on the porous border unless the 70,000 international forces in Afghanistan go after safe havens inside Pakistan.

Asked if Islamabad would allow NATO-led multinational troops to carry out its military operations on its soil, Zardari said his country was able to contain the insurgency.

"To the world we say: Help us; we can fight, we can look after ourselves, we know our terrain, we have our strength, all we need is the support," Zardari said, adding: "So give us the proper support, we can do the job better, cheaper than you can do it."

The Afghan and Pakistani sides on Tuesday also signed a joint declaration which emphasized enhanced cooperation and good-neighborly relations between the two Islamic nations.

This is the third time the two leaders have met in the past four months. Karzai attended Zardari's inauguration in September and the two met in New York on the sidelines of UN general assembly and in Turkey.

On his first visit to Afghanistan, Zardari was honoured with a gun salute upon his arrival in the presidential palace. Kabul residents were informed of the practice in advance in order to avoid panic in the city, which has suffered several terrorist attacks in the past. (dpa)