WASHINGTON (AFP) - A top US lawmaker said Tuesday that Pakistan must show seriousness of purpose against Taliban and their allies and Afghanistan must do more against corruption ahead of tough three-way talks in Washington. I think theres a continuing concern as to whether or not ... we can be successful in these two countries, Democratic House Majority Leader Steny Hoyer told reporters. Hoyer said he and his colleagues specifically have doubts about the impact of US aid to both countries and worry about whether the governments in Islamabad and Kabul are willing and able to fight extremists. We need to be very concerned about the dollars that were spending and the effectiveness of those dollars, he said, as Pakistans President Asif Ali Zardari and Afghan President Hamid Karzai were to meet lawmakers. All of us have concerns about the ability of the incumbent governments to get the job done, to attain the objective, which is obviously security and stability of those governments, defeat of the Taliban in both countries, said Hoyer. Hoyer said the US public wants to know that the Pakistanis are serious about defeating extremists and stabilising their nuclear-armed country, warning that the US cannot do that for its ally. Weve got to see a seriousness of purpose by the Pakistani government, by the Pakistani military, by the Pakistan security forces in pursuing stability themselves, he said. There is far too much focus by the Pakistan Army on India, on the Indian border. Their problems are coming from within, their northeast rather than their southeast and in their west, in the Fata, he said, referring to the Federally-Administered Tribal Areas. Hoyer also had some tough talk for Karzai, saying the Afghan President certainly says a lot of the right things but has not done enough to fight corruption. Theres still a lot of corruption that is a concern of our government - not necessarily Karzai himself, I dont mean that, I dont want to imply that, and Im not saying that, said Hoyer.