diff --git a/src/api/dart_ffi.rs b/src/api/dart_ffi.rs
index 0227a06..141bb3e 100644
--- a/src/api/dart_ffi.rs
+++ b/src/api/dart_ffi.rs
@@ -1,5 +1,5 @@
 use crate::coinconfig::{init_coin, CoinConfig};
-use crate::{broadcast_tx, ChainError};
+use crate::{broadcast_tx, ChainError, Tx};
 use allo_isolate::{ffi, IntoDart};
 use android_logger::Config;
 use lazy_static::lazy_static;
@@ -331,9 +331,9 @@ pub async unsafe extern "C" fn prepare_multi_payment(
             &recipients,
             use_transparent,
             anchor_offset,
-        )
-        .await?;
-        Ok(tx)
+        ).await?;
+        let tx_str = serde_json::to_string(&tx)?;
+        Ok(tx_str)
     };
     to_c_str(log_string(res.await))
 }
@@ -346,8 +346,9 @@ pub async unsafe extern "C" fn sign(tx_filename: *mut c_char, port: i64) -> *mut
         let mut file = std::fs::File::open(&tx_filename.to_string())?;
         let mut s = String::new();
         file.read_to_string(&mut s)?;
+        let tx: Tx = serde_json::from_str(&s)?;
         let raw_tx = crate::api::payment::sign_only_multi_payment(
-            &s,
+            &tx,
             Box::new(move |progress| {
                 report_progress(progress, port);
             }),
diff --git a/src/api/payment.rs b/src/api/payment.rs
index c8943ad..0f8b481 100644
--- a/src/api/payment.rs
+++ b/src/api/payment.rs
@@ -80,18 +80,18 @@ pub async fn build_only_multi_payment(
     recipients: &[RecipientMemo],
     use_transparent: bool,
     anchor_offset: u32,
-) -> anyhow::Result<String> {
+) -> anyhow::Result<Tx> {
     let (tx, _) =
         prepare_multi_payment(last_height, recipients, use_transparent, anchor_offset).await?;
-    let tx_str = serde_json::to_string(&tx)?;
-    Ok(tx_str)
+    // let tx_str = serde_json::to_string(&tx)?;
+    Ok(tx)
 }
 
 pub async fn sign_only_multi_payment(
-    tx_string: &str,
+    tx: &Tx,
     progress_callback: PaymentProgressCallback,
 ) -> anyhow::Result<Vec<u8>> {
-    let tx = serde_json::from_str::<Tx>(tx_string)?;
+    // let tx = serde_json::from_str::<Tx>(tx_string)?;
     let raw_tx = sign(&tx, progress_callback)?;
     Ok(raw_tx)
 }
diff --git a/src/main/rpc.rs b/src/main/rpc.rs
index a716787..982faa5 100644
--- a/src/main/rpc.rs
+++ b/src/main/rpc.rs
@@ -11,7 +11,7 @@ use std::collections::HashMap;
 use thiserror::Error;
 use warp_api_ffi::api::payment::{Recipient, RecipientMemo};
 use warp_api_ffi::api::payment_uri::PaymentURI;
-use warp_api_ffi::{AccountRec, CoinConfig, TxRec};
+use warp_api_ffi::{AccountRec, CoinConfig, Tx, TxRec};
 
 #[derive(Debug, Error)]
 pub enum Error {
@@ -60,7 +60,6 @@ async fn main() -> anyhow::Result<()> {
         .mount(
             "/",
             routes![
-                set_lwd,
                 set_active,
                 new_account,
                 list_accounts,
@@ -73,6 +72,8 @@ async fn main() -> anyhow::Result<()> {
                 get_tx_history,
                 pay,
                 mark_synced,
+                create_offline_tx,
+                sign_offline_tx,
                 broadcast_tx,
                 new_diversified_address,
                 make_payment_uri,
@@ -86,11 +87,6 @@ async fn main() -> anyhow::Result<()> {
     Ok(())
 }
 
-#[post("/set_lwd?<coin>&<lwd_url>")]
-pub fn set_lwd(coin: u8, lwd_url: String) {
-    warp_api_ffi::set_coin_lwd_url(coin, &lwd_url);
-}
-
 #[post("/set_active?<coin>&<id_account>")]
 pub fn set_active(coin: u8, id_account: u32) {
     warp_api_ffi::set_active_account(coin, id_account);
@@ -179,6 +175,33 @@ pub fn get_balance() -> Result<String, Error> {
     Ok(balance.to_string())
 }
 
+#[post("/create_offline_tx", data = "<payment>")]
+pub async fn create_offline_tx(payment: Json<Payment>) -> Result<Json<Tx>, Error> {
+    let c = CoinConfig::get_active();
+    let latest = warp_api_ffi::api::sync::get_latest_height().await?;
+    let from = {
+        let db = c.db()?;
+        db.get_address(c.id_account)?
+    };
+    let recipients: Vec<_> = payment
+        .recipients
+        .iter()
+        .map(|p| RecipientMemo::from_recipient(&from, p))
+        .collect();
+    let tx = warp_api_ffi::api::payment::build_only_multi_payment(latest, &recipients, false, payment.confirmations).await?;
+    Ok(Json(tx))
+}
+
+#[post("/sign_offline_tx", data = "<tx>")]
+pub async fn sign_offline_tx(tx: Json<Tx>, config: &State<Config>) -> Result<String, Error> {
+    if !config.allow_send {
+        Err(anyhow!("Payment API not enabled").into())
+    } else {
+        let tx_hex = warp_api_ffi::api::payment::sign_only_multi_payment(&tx, Box::new(|_| {})).await?;
+        Ok(hex::encode(tx_hex))
+    }
+}
+
 #[post("/pay", data = "<payment>")]
 pub async fn pay(payment: Json<Payment>, config: &State<Config>) -> Result<String, Error> {
     if !config.allow_send {