US President Barack Obama has offered to help Yemen in its “fight against terrorism” and assist the country with its reforms, the Yemeni state news agency Saba said late on Sunday. “Yemen's security is vital to the security of the United States and the region, and America will adopt an initiative to help Yemen ... face development challenges and support reform efforts,” Obama said in a letter delivered by his counterterrorism adviser John Brennan to Yemeni President Ali Abdullah Saleh. The letter said the United States will “stand beside Yemen, its unity, security and stability.” The Arab world's poorest country is battling a Zaidi revolt in the north, separatist unrest in the south, and intensified Al-Qaeda militancy. International concern over Yemen has heightened because instability there could endanger neighbors and complicate efforts to combat Al-Qaeda and piracy in the Gulf of Aden. The US leader “hailed the established partnership between the two friendly countries in the field of fighting terrorism,” pointing out that “Al-Qaeda organization is a common threat and dangerous to everyone,” it said. Yemen has witnessed a number of attacks claimed by Al-Qaeda against foreign missions, tourist sites and oil installations. In August, a new wave of fighting erupted between rebels of the Zaidi sect and government forces trying to impose central authority. The conflict first began in 2004. A Yemeni official said Brennan discussed with Saleh the importance of Yemen's continuation of economic and political reforms. The meeting discussed Yemen's counterterrorism efforts and the assistance the US might offer in this regard, without giving further details, the official said.