The increasing penetration of distributed energy sources in electric power and natural gas distribution networks in recent years has led to a shift from the conventional centralized trading mode to decentralized trading. However

current decentralized energy trading developments

such as those based on the peer-to-peer (P2P) paradigm

have mainly focused on electric power grids

while regional integrated energy systems coupled by multiple energy sources are currently restricted to centralized scheduling generally. This present work addresses this issue by developing a P2P market transaction model for regional integrated energy systems. First

the privacy of each participating agent is preserved by conducting a trade matching process between producers and consumers

and the P2P trading strategy is constructed. Then

the feasibility of the obtained trading strategy is confirmed by the operation center of the regional integrated energy system by conducting collaborative optimization scheduling based on the P2P energy trading results. Moreover

the locational marginal price is employed to calculate the P2P network usage charge. This charge is then equally distributed between producers and consumers to incentivize balanced utilization of the distribution network and ensure equitable benefits from P2P transactions. The effectiveness and superiority of the proposed P2P trading framework are demonstrated based on numerical results obtained for realistic regional integrated electric and natural gas systems.